Prerpints.org logo
Preprint
Review

This version is not peer-reviewed.

Plant and Animal Derived Organic Waste as Fillers in Biodegradable Composites for Advanced Applications: A Comprehensive Overview

A peer-reviewed article of this preprint also exists.

Submitted:

01 December 2025

Posted:

01 December 2025

You are already at the latest version

Abstract
Biodegradable polymeric composites reinforced with natural fillers represent one of the most promising routes toward low-impact, circular, and resource-efficient materials. In recent years, a growing number of studies has focused on the valorization of plant- and animal-derived organic waste, ranging from agricultural residues and natural fibers to marine and livestock by-products. This review provides a comprehensive and compar-ative overview of these systems, analyzing the nature and origin of the waste-derived fillers, their pretreatments, processing strategies, and the resulting effects on mechanical, thermal, functional, and biodegradation properties. Particular attention is dedicated to the role of filler composition, morphology, and surface chemistry in governing interfacial adhesion and end-use performance across different polymeric matrices, including PLA, PCL, PBS, PHA, PHB, PBAT, and commercial blends such as Mater-Bi®. The emerging applications of these biocomposites, such as packaging, additive manufacturing, agri-culture, biomedical uses, and environmental remediation, are critically discussed. Overall, this work provides fundamental insights to support the development of the next generation of biodegradable materials enabling the sustainable valorization of organic waste within a circular-economy perspective.
Keywords: 
biodegradable biocomposites
;  
circular economy
;  
green composites
;  
natural fillers
;  
sustainable materials
;  
waste valorization
Subject: 
Chemistry and Materials Science  -   Materials Science and Technology

1. Introduction

The global dependence on petroleum-derived plastics has led to unprecedented levels of environmental pollution, resource depletion, and waste accumulation [1,2]. Over the past decades, plastic production has grown exponentially, surpassing 400 million tons per year, while recycling rates have remained critically low [3]. Figure 1 provides an overview of European plastic production in 2022 (60 Mt) and its subsequent conversion into different application sectors. As shown, the European plastics sector alone remains strongly dominated by fossil-based and non-biodegradable polymers (80.3%), which continue to accumulate in landfills and natural ecosystems due to their slow degradation rates and inefficient end-of-life management strategies. Only a minor fraction derives from bio-based feedstocks (1%) or mechanically recycled materials (12.9%). The right-hand chart highlights how polymeric materials are predominantly used in packaging (40%), followed by the building sector (23%) and a range of industrial applications including automotive, electrical, agriculture, and household products [4]. Overall, the figure underscores the continued reliance on fossil-based polymers. In parallel, increasing awareness and stricter environmental regulations are intensifying the demand for sustainable alternatives that can reduce the ecological footprint of materials while maintaining performance standards.
Within this context, biodegradable and bio-based polymers have emerged as promising candidates to replace traditional plastics in a wide range of applications. Polymers such as polylactic acid (PLA), polycaprolactone (PCL), poly(butylene succinate) (PBS), polyhydroxyalkanoates (PHAs), polyhydroxybutyrate (PHB), poly(butylene adipate-co-terephthalate) (PBAT), and thermoplastic starch combine a reduced environmental impact with mechanical and thermal properties often comparable to those of conventional petrochemical polymers [5,6,7]. However, despite these advantages, biopolymers still present important limitations including brittleness, limited thermal resistance, moderate barrier properties, and relatively high production costs which can restrict their technological applicability in demanding sectors [5,6,7]. To overcome these limitations, the scientific community has increasingly focused on biocomposites, materials obtained by reinforcing biodegradable polymer matrices with natural fillers [8]. This approach enables the development of systems that are not only more sustainable, but also exhibit enhanced mechanical, thermal, functional, and degradation properties. More in detail, the addition of low-cost fillers improves stiffness, strength, or toughness [9,10,11]; may enhance barrier or antioxidant capabilities; enable environmental remediation ability [12]; and can modulate biodegradation kinetics [13,14]. Importantly, the environmental benefits are maximized when the fillers themselves originate from waste biomasses, enabling a dual advantage: valorizing organic waste and lowering the environmental and economic cost of composite production.
In this framework, plant- and animal-derived organic waste represents an abundant, renewable, and largely underutilized resource. Natural fillers include different type of materials: from agricultural residues such as peels, husks, fibers, and lignocellulosic fractions, to marine and animal by-products including shells, bones, gelatin, and wool. These materials are generated in massive quantities globally. Agro-food industries produce millions of tons of lignocellulosic residues annually, while fisheries, aquaculture, and livestock sectors generate shells, bones, feathers, and wool scraps that are often disposed of at high environmental and economic cost [15,16]. When properly treated, these waste-derived fillers offer mechanical reinforcement, functional properties or may act as nucleating agents that accelerate polymer crystallization and biodegradation [17]. Plant-derived wastes, rich in cellulose, hemicellulose, and lignin, generally show good compatibility with biodegradable polyesters and are valued for their reinforcing effect, low density, and availability at negligible cost [18]. On the other hand, animal-derived wastes contain minerals (e.g., CaCO₃ in shells, hydroxyapatite in fish bones) and proteins (e.g., collagen, keratin, chitin), which can impart unique properties such as increased stiffness, bioactivity, biocompatibility, or enhanced degradability [15]. Furthermore, several studies have demonstrated that these fillers can enable advanced functionalities, making biocomposites suitable for packaging, agriculture, biomedical devices, additive manufacturing (3D printing), air filtration, and environmental remediation [18,19].
Despite the growing interest and the remarkable progress achieved in the field, several challenges remain unresolved. Organic waste streams are inherently heterogeneous in chemical composition, particle size, moisture content, and morphology. These factors strongly influence their compatibility with polymer matrices and the reproducibility of the final composites. Pretreatments are not always adopted, leading to difficulties in comparing results across studies. Additionally, the correlation between filler characteristics, processing methods, and final composite properties is not yet fully understood and often requires systematic investigation. Finally, while biodegradation is a key feature of these systems, comprehensive environmental assessments, such as life-cycle analysis (LCA), are still underrepresented in the literature.

1.1. Background and Motivation

The valorization of organic waste within polymer composites aligns with global strategies for circular economy, zero-waste approaches, and resource-efficient materials design. By transforming residues into functional components, waste is reconceptualized not as a disposal issue but as a valuable raw material contributing to high-performance bio-based materials. This approach not only minimizes environmental impacts but also offers economic benefits for industries seeking sustainable alternatives and novel value chains.

1.2. Objective of the Review

Based on these considerations, this review aims to provide a comprehensive over-view of the use of plant- and animal-derived organic waste as fillers in biodegradable biocomposites. Specifically, it analyzes:
  • the types, characteristics, and pretreatments of natural fillers;
  • the processing strategies employed across different polymer matrices;
  • the resulting mechanical, thermal, morphological, functional, and degradation properties;
  • the main applications and end-of-life scenarios;
  • current challenges, limitations, and future research directions.
By mapping the state of the art across plant and animal fillers, this review aims to offer a solid basis for the design of next-generation biocomposites and to stimulate further research toward the sustainable valorization of organic waste resources.

2. Biodegradable Polymeric Matrices for Biocomposites Production

Polymer composites can fall into different categories depending on both the origin of the matrix and their end-of-life behavior, as illustrated in Figure 2. Materials may be bio-based or fossil-based, and independently, they may be biodegradable or non-biodegradable. This classification highlights that “bioplastics” is an umbrella term that includes multiple families of materials: bio-based but non-biodegradable composites (such as those derived from bio-PE or bio-PET), fully bio-based and biodegradable systems (e.g., PLA, starch-based blends, PHAs), and even fossil-based biodegradable polymers such as PBAT and PCL. Understanding these distinctions is crucial when designing sustainable biocomposites, since the environmental profile of a material depends not only on the renewable origin of its constituents but also on its degradability and disposal routes.
Biodegradable polymers are a class of materials considered a promising alternative to conventional polymers. Indeed, their main advantage is their ability to biodegrade under suitable conditions, which helps reduce plastic waste and environmental impact. Moreover, many of these materials offer performance that are comparable to, or some-times even better than, conventional polymers. The most commonly available on the market and reported biodegradable polymers include polylactic acid (PLA) [20,21,22,23,24,25,26], poly-caprolactone (PCL) [27,28,29], poly(butylene succinate) (PBS) [30,31,32,33], polyhydroxyalkanoates (PHAs) [34,35], poly(butylene adipate-co-terephthalate (PBAT) [36,37,38,39] and thermoplastic starch (TPS) [40,41]. Each polymer presents different characteristics and can be used in various industrial fields. Undoubtedly, PLA is one of the most widely used polymers, partly due to its widespread availability on the market. However, PLA, produced through the fermentation of sugars, is also valued for its stiffness, transparency, and good processability, and is widely used in packaging, disposable products, textiles, and biomedical items, although it still has limitations for more advanced engineering applications [20,21].
Equally used mainly in biomedical applications, controlled release systems, and as a component in polymer blends to improve toughness and processability is PCL [27,29], a biodegradable polyester with a low melting point and excellent flexibility. Instead, PBS produced from renewable or fossil-based monomers, combines biodegradability with good thermal and mechanical performance and is used in films, containers, and coatings [30,31]. PHAs form a large family of polyesters produced by microorganisms using renewable carbon sources. Their properties can differ widely depending on the specific type: for example, poly(3-hydroxybutyrate) (PHB) is typically tough and brittle [35], whereas copolymers such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) offer improved flexibility and toughness [42].
As regards the biodegradable polymers obtained from fossil monomers, PBAT is a biodegradable aromatic-aliphatic copolyester used in the production of films, shopping bags, agricultural films and compostable packaging [37]. It is characterized by high flexibility, strength, and good compatibility with other biodegradable polymers, particularly PLA and TPS [43]. The latter, obtained from starch sources such as corn or potatoes, is flexible, biodegradable, and particularly suitable for food packaging, edible films, and simple consumer products [40,41].

3. Natural Waste Fillers in Biocomposites

The development of biocomposites involves the use of natural raw materials and processing methods to improve their performance and sustainability. This section introduces the main categories of organic waste, both plant and animal, used as fillers, together with the processing strategies adopted to date to improve their compatibility and functionality. Figure 3 provides an overview of the broad variety of natural waste fillers currently explored for biocomposite production.
These materials can be grouped into plant-based and animal-based resources, each encompassing several derived subcategories. Plant-based fillers include agricultural residues (such as almond shells, rice husk, and tomato peels) [16,18], natural fibers (e.g., sisal, kenaf, jute, bamboo) [44,45], cellulose-rich derivatives (lignin, paper waste, nanocellulose) [46,47], and alternative plant by-products such as Posidonia Oceanica leaves or babassu fibers [48,49]. On the other hand, animal-based sources include shells from poultry and seafood processing (eggs, crab, oyster) [50], fish waste (fish gelatin, bones) and wool or fur residues from livestock or textile sector [8,15]. This classification highlights the wide diversity and abundance of natural waste streams available for sustainable composite manufacturing, emphasizing how both plant- and animal-derived by-products can be effectively valorized as functional fillers.

3.1. Plant-Derived Organic Waste

Plant-derived organic waste includes a wide variety of plant residues, which can be classified into four main groups, such as: agricultural and agrifood waste, natural fibers, cellulose and derivatives and alternative organic waste.

3.1.1. Agricultural and Agrifood Waste

Currently, the valorization of agricultural and agrifood waste is a key strategy to promote the sustainability of their supply chains. Indeed, it is estimated that around 180 million tons of agricultural and agrifood waste are generated each year in Europe [16], of which a significant part is made up of residues such as: peels, stems, seeds, skins and shells from collecting and processing. However, the most recent data estimate that approximately 40 % of them is currently not properly valorized [16]. As a result, the possibility of valorizing this waste is increasingly a real opportunity. Nonetheless, they range from fibrous materials to a more compact and denser fractions with irregular particle size and variable porosity. For this reason, to make them compatible with processing, it is necessary to subject them to preliminary treatments, such as: drying, grinding - to powder or particles - and in some cases even chemical treatments or addition of additives and/or compatibilized to improve adhesion to the matrices. In Table 1 relevant studies regarding biocomposite based on agricultural waste fillers are reported.
Almost 61.7 % of the agricultural and agrifood waste used originate from Europe, 27.7 % from Asia, 8.5 % from South America, and 2.1 % from North America. Among the agricultural by-products most employed to produce biodegradable composites, rice husk [64,65,66,67,68,82,83] and nutshell-derived fillers [56,57,78,80,83,88,89,91,95] such as hazelnut and almond shells are among the most widely investigated. Fruit-processing residues, especially peels and seeds, are also widely explored as bio-fillers, with a particular emphasis on citrus by-products and other fruit species that are characteristic of specific local supply chains [52,55,59,63,70,74,76,81,86,90]. Recent studies also report fillers obtained from crop harvesting residues, such as tomato [71,94], corn [85,87], artichoke [51], and other vegetable by-products [69,79], as well as wastes generated during olive processing for table olives and oil production [60,74]. Several studies have also explored natural fillers derived from Mediterranean plant species, including Opuntia ficus indica [61,62,93] and Hedysarum coronarium [58,92], which have gained attention due to their abundance, low cost, and easy incorporation in biodegradable polymer matrices. Additional examples include fillers obtained from cocoa-processing residues [53,54,77], such as bean shells and husks. Moreover, several other isolated cases of agricultural waste filler have been reported in the literature [72,73,75,83,84], which highlight the broad diversity of agrowaste-derived materials being investigated for biodegradable composite formulations.
The mechanical pretreatments used for prepare the filler involved grinding or knife milling, sometimes also ultracentrifugal (UC) [56,60,70,83] or high speed (HS) [62,95] milling followed by sieving. Drying was typically carried out at temperatures ranging from 40 °C up to 80 °C, with some studies reaching temperatures above 100°C [66,82,88,89] with drying times between 6 h and 72 h. In some cases, the drying step was not specified or was omitted. Some examples of ground waste materials are shown in Figure 4.
Moreover, in certain studies, additional treatments, such as alkali treatment or coupling agent application, were also performed. For instance, rice husk (RH) has been treated with a coupling agent to improve the properties of the biocomposites [64]. Similarly, in another study [65] both the rice husk (RH, Figure 4a) and PLA were treated with silane coupling agents (KH550 and KH570) to enhance the interfacial surface quality. Even for rice straw [66,67], tangerines [70], apple pomace [76], and almond shells [78,80], coupling agents were applied to improve interfacial adhesion. Alkaline treatments were also performed to remove undesired components from tomato peels (THP) and pineapple leaf (PL) [71,81].

3.1.2. Natural Fibers

A valid alternative to synthetic fibers are today represented by natural fibers which, thanks to their biodegradability and especially their low cost, are increasingly used in various applications (see Figure 5). Table 2 offers a comprehensive summary of studies focused on the use of natural fibers for biodegradable composites production. Only 28.2 % of the works consider fibers originating from Europe, while 48.7 % from Asia, 15.4 % from South America, and 7.7 % from Africa.
Table 2. Matrices, fillers, and treatments of biocomposites based on natural fibers waste.
Table 2. Matrices, fillers, and treatments of biocomposites based on natural fibers waste.
Matrix Filler Sample Code Area Type
(*) 		Diameter [um] Length
[mm] 		Density [g/cm3] Other
Treatments 		Additive Ref.
PLA Abutilon
indicum		 PLA/AI Asia D` - 2.5 - - - [96]
PLA Agave
PLA/AF South America - - - - - - [97]
PLA Bamboo PLA/BF Asia D - 2−6 - Chemical - [98]
PLA Bamboo PLA/BF Asia D - 2−6 - Chemical - [99]
PLA Corn stalk PLA/CS Europe D - 1−4 - - - [100]
PLA Elephant grass PLA/EG Asia D 250 3 - Mercerization and Bleaching - [101]
PLA Flax PLA/CFY Asia C 400 20 - - - [102]
PLA Flax PLA/Flax Europe D - - - - - [103]
PLA Flax PLA/FS Europe C - - 1.47 - - [104]
PLA Flax PLA/FS Europe D 300−600 2−5 - - Plasticizer [105]
PLA Hemp shives PLA/HS Europe D - < 1 1.51 - - [106]
PLA Himalaya
calamus
falconeri		 PLA/THF Asia D - 3−5 - Mechanical extraction - [107]
PLA Jute PLA/Jute Europe D - - - - - [103]
PLA Kenaf PLA/KF Asia D 250 - - - - [108]
PLA Kenaf PLA/KF Asia D 70−250 - - - - [109]
PLA Kenaf PLA/KFA Asia D - - - Acetylation Acetic
anhydride		 [110]
PLA Kenaf PLA/LK Asia C - 175 - - - [111]
PLA Kenaf
(woven)		 PLA/WK Asia D - - - - - [112]
PLA Pennisetum
setaceum		 PLA/PS Europe D 75 1−2 - - - [113]
PLA Sisal PLA/SF Asia D - 3−6 1,24 Pretreatment - [114]
PLA Sisal PLA/SF Asia D - 3−8 - - - [115]
PLA Sisal PLA/SF Africa D 239 - - - - [116]
PLA Sisal PLA/MS Africa D 239 - 1.42 - - [117]
PCL Date palm PCL/DP Asia D - 10 0.9−1.2 - - [118]
PCL Hemp PCL/HF Europe D 22 < 1 - - - [119]
PCL Phoenix
dactylifera L.		 PCL/DP Asia D - 10 0.92 - - [120]
PBS Curaua PBS/C South America D - 10−40 - - - [121]
PBS Hemp PBS/HF Europe D - 30 - - - [122]
PHA Pineapple
leaf		 PHA/PLF Asia D 300−450 - - - - [81]
PHB Sisal PHB/SF Asia D - - - - - [123]
PHBV Alfa PHBV/AF Africa D - - - Chemical - [124]
PBAT Croton
lanjouwensis		 PBAT/CF South America D - - 1.5 - - [125]
PBAT Malvastrum tomentosum PBAT/MF South America D - - 1.5 - - [125]
PBAT Trema
micrantha		 PBAT/TF South America D - - 1.5 - - [125]
PBAT Cannabis
sativa		 PBAT/CS Europe D < 32 - - - - [126]
PBAT Hemp PBAT/HF Asia D - - - Surface
alkylation		 Silane
coupling agent		 [127]
PBAT Kenaf PBAT/KF Asia D - 1−5 - - - [128]
PBAT Linum PBAT/F Europe D 1 - - - [129]
Mater-Bi® Agave MB/AF South America D - 4−6 - - - [130]
(*) D: discontinuous; C: continuous.
Preprints 187577 g005
Figure 5. Close-up photos of abutilon indicum (a), corn stalk (b) and date palm (c) fibers. Reprinted (adapted) with permission from [96,100,118].
Figure 5. Close-up photos of abutilon indicum (a), corn stalk (b) and date palm (c) fibers. Reprinted (adapted) with permission from [96,100,118].
Preprints 187577 g005
Most of the natural fillers employed generally come from agricultural residues or from low environmental impact collects. Naturally, although most natural fibers are short, their properties—such as diameter, length, and morphology—significantly influence their effectiveness as reinforcements. Consequently, natural fibers are increasingly subjected to preliminary characterization and, in some cases, to treatments to enhance their adhesion to the polymer matrix before use. For instance, bamboo fibers [98,99] have been chemical treated by immersing them for 4 hours in an aqueous solution containing 2% NaOH. Subsequently, they were rinsed with distilled water to remove any remaining impurities. Prior to processing, the fibers were oven-dried to eliminate residual moisture.
Flax [102,103,104,105,129] and kenaf [108,109,110,111,112,128] fibers are widely employed in composite manufacturing, either untreated or after undergoing chemical or physical modifications. Notably, kenaf fibers were oven-dried for 24 h at 80 °C to remove excess moisture and then stored in polyethylene bags to prevent water vapor absorption [110]. Subsequently, 40 g of dried fibers were reacted with acetic anhydride in the presence of pyridine as a catalyst, under reflux at 145 °C for different reaction times. After the reaction, the fibers were washed with distilled water and 80% ethanol to remove residual reagents and then dried in a vacuum oven at 60°C overnight.
Similarly, sisal [114,115,116,117,123] fibers have been broadly adopted in the production of composite materials due to their favorable mechanical and morphological characteristics. In most cases, the fibers have been employed without any pre-treatment or with simple pretreatment involving water to remove dirt and pith from the fiber surface, followed by sunlight drying for 48 hours to remove moisture [114]. In this latter case, before processing with the matrix, the fibers were heated to 80°C in a ventilated environment for 6 hours.
Hemp [115,119,122,127] fibers also represent a well-established reinforcement in the field of polymer composites. In this case as well, some examples report the use of fibers subjected to pre-treatment prior to processing. In a recent study [127], hemp fibers have been subjected to a two-step treatment. In the first step, an alkali treatment was performed by immersing the fibers in a 10% NaOH solution at 10 °C for 1 hour, followed by washing and oven-drying at 80 °C in preparation for the subsequent step. In the second step, the fibers were treated with a coupling agent to enhance the interfacial properties.
Beyond widely used fibers such as jute [103], numerous studies have explored less conventional, locally available alternatives aimed at valorizing regional agricultural residues. Examples include agave [97,130], date palm [118], cannabis sativa [126], pineapple leaf [81], and other location-specific sources [96,100,113,120,121,125]. These fibers can be employed in their untreated form. However, several works also report the adoption of pre-treatment or surface-modification steps to enhance the compatibility and performance of alternative fibers within composite systems. For instance, elephant grass fibers were subjected to a mercerization treatment [101]. The treatment involved immersing 200 g of elephant grass fibers in a 10% NaOH solution for 6 hours at 70 °C under continuous shaking and stirring, followed by neutralization with 50% acetic acid to remove any absorbed alkali. Finally, the fibers were thoroughly washed with deionized water. Moreover, a bleaching treatment was performed using hydrogen peroxide at room temperature, followed by thorough washing with distilled water and drying in an oven at 50 °C. Moreover, Himalaya Calamus falconeri fibers were isolated from the culms using a water-retting process followed by mechanical extraction [107]. In this study, a surface modification using a NaOH solution for 5 hours at 30 °C was performed to investigate the effect of the alkali treatment on the properties of the biocomposites. In addition, alpha fibers were treated using an in-house optimized method [125]. The fibers were treated with 2% NaOH in water for one hour and then washed several times with distilled water containing 1% acetic acid to neutralize the sodium hydroxide. Finally, they were washed with distilled water until neutral pH was achieved and dried in an oven at 80°C for 6 hours.

3.1.3. Cellulose and Derivatives

Compared to agricultural and agrifood wastes and natural fibers, only a few studies have focused on cellulose and its derivatives. However, cellulose and lignin are an attractive renewable resource that could be employed for the production of biocomposites since they are the main by-product of the pulp and paper industry [46,47,131,132]. The Table 3 summarizes the studies available in the literature regarding the use of cellulose and its derivatives as fillers in biocomposites.
Nevertheless, these limited studies have explored cellulose extracted from a diverse range of sources, including: Eucalyptus grandis [133], E. autumnalis (see Figure 6a,b) [134], corn cob [135], residues from the paper and paperboard industry (see Figure 6a,b) [137,138], durian husk [139], agricultural waste [140], Luffa cylindrica [141], black liquor [142], softwood almond shells [143], potato peel [92], and coconut fiber [145]. In other cases, commercial cellulose has been used [136].
Mechanical treatments typically involved grinding and sieving [134,139,140,143,144] and in most cases, oven-dried at temperatures between 60 and 100 °C for 12-24 hours, prior to processing. Moreover, in many cases it was subjected to treatments that included: sodium chloride [134], bleaching [137], combination of alkaline and bleaching [139,145] and fatty acid ester [138] to improved their compatibility with polymer matrices. Plasticizers [135] or compatibilizers [141] were also used.

3.1.4. Alternative Plant-Derived Waste

Recently, although still relatively limited, filler research has increasingly focused on exploring alternative plant-derived wastes as sustainable reinforcements in biocomposites (see Table 4).
Posidonia oceanica (see Figure 7) has been incorporated as a filler with the dual purpose of mitigating disposal problems and enhancing valorization opportunities [146,147,148,150]. Moreover, some fillers, such as aloe [149], algae [151] and other [152,153], were employed as fillers taking advantage of the presence of intrinsic compounds that can exert a plasticizing effect. As reported in Table 4, in many cases mechanical treatments were applied, such as grinding and sieving, followed by drying at temperatures between 60 and 90 °C for 12-24 hours.

3.2. Animal-Derived Waste

Although most studies have focused on plant-derived fillers, animal-derived organic waste has recently gained growing attention as a valuable resource for developing biodegradable and functional biocomposites. Large quantities of residues are generated annually from the fish, shellfish, poultry, and livestock sectors, including bones, shells, eggshells, feathers, and wool fibers. These by-products, contain minerals and proteins, such as calcium carbonate, collagen, chitin, and keratin, which exhibit distinctive chemical compositions and morphologies.
Table 5. Matrices, fillers, and treatments of biocomposites based on animal waste.
Table 5. Matrices, fillers, and treatments of biocomposites based on animal waste.
Matrix Filler Sample Code Area Mechanical Treatment Drying Temp. [°C] Drying Time [h] Other
Treatments 		Ref.
PLA Eggshell PLA/WE N. America Ground 80 4 - [154]
PLA Eggshell PLA/ESP Asia Ground - - - [155]
PLA Eggshell PLA/WES N. America Ground - - - [156]
PLA Fish gelatin PLA/FG Europe - 80 12 [157]
PLA P. undulata shell PLA/PUS Asia Ground 100 / 60 24 / 48 Calcination [158]
PLA Crab shells PLA/CSP Asia Ground 60 12 HCl, NaOH [159]
PLA Anchovy fish bone PLA/EE Europe Ground 60 12 - [160]
PLA Wool PLA/WP Europe Ground 60 12 - [161]
PHA Oyster shell PHA/OSP Asia Ground - - - [81]
Mater-Bi® Anchovy fish bone MB/EE Europe Ground 60 12 - [160]
HCl: hydrochloric acid; NaOH: sodium hydroxide.
Relevant examples of biocomposites based on animal derived filler are listed in Table 5. Among them, numerous formulations based on PLA and eggshell powders are reported (see Figure 8) [154,155,156]. Eggshell are mainly composed of calcium carbonate and minor amounts of organic proteins. Up to 10% waste eggshell was successfully incorporated into a PLA matrix [154]. Moreover, marine residues such as oyster [81], crab [159], or mollusk [158] shells —rich in chitin, chitosan, and calcium salts — have been successfully added to PLA or PHA matrices. Fish-processing wastes, such as bones [160] or gelatin [157], containing hydroxyapatite or collagen, and other nitrogen-based molecules, have been used as fillers in PLA and Mater-Bi® based composite. In addition, wool waste powder, obtained from sheep fur not suitable for textile production, was added to PLA solution as functional filler [161]. Wool is rich in keratin proteins and can be processed in fibrous or powdered form.
Similarly to what has been observed with plant-based waste, animal wastes generally undergo drying, grinding, and sieving before being used as fillers. In the case of shell powders, additional treatments such as calcination, acid–base purification, or deproteinization are often applied to remove residual impurities and to improve interfacial adhesion with the polymer matrix [158,159]. The resulting powders or fibers exhibit a wide range of densities, particle sizes, and surface chemistries, which influence their processability and dispersion within polymeric matrices.

4. Processing, Properties Application and End of Life of the Natural Waste Based Biocomposites

The performance of natural-waste-based biocomposites strongly depends on the correlation between filler characteristics, processing parameters, and the adopted manufacturing technique. In this section, the main processing routes, the resulting mechanical and functional properties, and the application fields of these materials are critically reviewed. Particular attention is given to how the intrinsic nature of each waste-derived filler influences composite performance and end-of-life behavior, including biodegradation and disintegration.

4.1. Plant-Derived Organic Waste

4.1.1. Agricultural and Agrifood Waste

The use of agricultural and agro-industrial residues as fillers in biocomposites represents a promising strategy to enhance material performance while providing environmental and economic benefits.
As summarized in Table 6, several studies have investigated the incorporation of these wastes into different polymer matrices. Undoubtedly, PLA is the most commonly used matrix, together with commercial blend Mater-Bi. It is followed by PCL, PBS, PHA, PHB and finally PBAT. In most cases, melt compounding (MC) was used in combination with various molding processes: compression [58,62,66,75,85,86,90], injection [52,56,57,59,67,70,76,78,79,80,84,87,91,95] and hot process [51,74,81,82,83]; while some studies used 3D printing to manufacture filaments or complex structures [53,54,58,60,61,64,65,68,77,92,93,94]. In very few cases, films were obtained using MC combined with film blowing [55] or solvent casting [63,69].
In PLA-based composites, the incorporation of fillers such as: artichoke plant [51] banana [52], hazelnut shells [56,57], hedysarum coronarium [58], mango seed [59], opuntia ficus indica [62], tangerines [70] and rice straws [66,67] using conventional molding techniques, has generally led to significant mechanical improvements, including increases in tensile [52] and flexural strength [52,56], and modulus [51,56,58,62]. In some cases, some fillers have also contributed to barrier performance [59] and sustainability [56,70], while offering the advantage of easy scalability [57]. On the other hand, PLA-based composites processed by using 3D printing and incorporation the following filler: cocoa husk and bean [53,54], rice husk and straw [64,65,68], olive wood [60], wheat middling and wastes [72,73] and Opuntia ficus indica [60,61] showed an increase in tensile strength [53,64,65,68] stiffness [54], flexural [68] proprieties, a good filler dispersion [72] and good processability [61]. In the case of PLA-based films, through melt compounding combined with film blowing or solvent casting, the fillers involved such as grape pomace [55], orange peel [63], sesame husk [69] and tomato peel [71], mainly improved the functional and environmental properties, including antioxidant and antimicrobial activity, [55] as well as biodegradability [63] and disintegration rate [69].
In PCL-based composites, conventional molding techniques with fillers such as date seed [74], olive stones [74], waste bean [75] and wheat bran [74] mainly improved the modulus and especially the thermal properties, while wheat bran also showed a plasticizing effect. Similarly, PBS-based composites, processed by injection molding or 3D printing with fillers such as apple pomace [76], cocoa bean shells [77], almond shell [78,80] and onion peel [79] have shown improvements in impact and tensile strength, elastic modulus, ductility, and disintegration rate, with some composites exhibiting accelerated biodegradation under soil conditions. Furthermore, the use of compatibilizers has improved ductility and mechanical performance [79,80].
Composites based on PHA [81,82], PHB [83], PHBV [84] and PBAT [85,86,87] were mostly processed by hot pressing, compression, or injection molding. These systems showed improvements in terms of mechanical properties, stiffness, thermal stability, permeability, and biodegradability, with several studies confirming the effectiveness of degradation in soil or compost as showed in Figure 9.
Finally, composites based on commercial blend Mater-Bi® (MB), processed via injection molding or 3D printing with fillers including almond shell [88,89], grape pomace [90], hazelnuts shells [91], hedysarum coronarium [92], opuntia ficus indica [93], and tomato plant [94], exhibited improvements in mechanical properties, ductility, rigidity, and fertilizer release [43], depending on the filler and selected matrix, see Figure 10.
Mainly, applications were focused on packaging [55,59,62,69,71,74,77,80,81,83,84,85,86,87,88,89] and 3D printing filaments [53,54,61,64,68,72,73,78,90,94], with some studies targeting the automotive [58,65] and industrial [51,56,60,74,75] sectors (see Figure 11).
Specifically, some studies have highlighted additional functionalities, such as fertilizer release in MB-based composites [93,94], as seen in Figure 9, or increased sustainability, with tests conducted in various environments, including soil burial [63,68,84,88], composting [70,95] and disintegration [69,78,83] studies.

4.1.2. Natural Fibers

The ongoing search for eco-sustainable materials is increasingly leading to the development of biocomposites based on biodegradable polymers and natural fillers. Indeed, the intrinsic reinforcement capacity of the used fillers (see Table 2), maintaining their biodegradability, helps reduce environmental impact and promote the sustainable use of renewable resources. Table 7 summarized recent studies on these systems, highlighting the relationship between processing, properties and end of life scenarios.
As already seen above, among the various matrices used, PLA remains undoubtedly the most studied, mainly thanks to its biobased origin, good processability and, above all, its wide availability on the market compared to other new biodegradable polymers.
PLA-based composites obtained by melt compounding followed by compression or injection molding exhibited generally significant improvements in mechanical performance [110,111,112,114,115,116,117]. For example, PLA reinforced with Abutilon indicum [96] or bamboo fiber [98,99] showed an increase in tensile and thermal resistance, especially when the filler content and fiber dispersion were optimized. Moreover, PLA reinforced with elephant grass [101], flax [103,104] and Falconeri [107] fibers showed an enhance tensile strength and stiffness, suggesting that high fiber tensile strength and chemical surface treatments are key factors governing stress transfer and interfacial bonding. Indeed, when untreated natural fibers are used, low interfacial adhesion can still limit the efficiency of reinforcement [100]. On the other hand, several studies have explored the use of these biocomposites in additive manufacturing. In particular, PLA reinforced with agave [97] and kenaf [108] fibers processed by 3D printing showed improved impact strength and stiffness, making these systems suitable candidates for functional components and filaments for fused deposition modeling (FDM). Similarly, PLA coated with continuous flax fibers (CFY) resulted in an increase in tensile modulus and, especially, structural integrity of printed parts [102]. Lower rotation speed during extrusion could improve the fiber aspect ratio, leading to an improvement in the mechanical properties of the 3D-printed filament [105]. Consequently, parameter control can be as a crucial as the filler choice in optimizing the performance of printed biocomposites.
In addition to mechanical performance, some works, have investigated the environmental the end-of-life cycle of these systems [109]. For example, PLA reinforced with elephant grass [101] and hemp shives [106] showed an increase in biodegradation rate under soil conditions, while the incorporation of Pennisetum setaceum [113] led to accelerated composting behavior. This indicates that some natural fillers can act as nucleating sites for microbial attack or moisture diffusion, thus promoting biodegradation. Nonetheless, despites these promising results, the end-of-life aspect remains unexplored for most PLA biocomposites.
Besides PLA, other biodegradable polymers such as PCL, PBS, PHA, PHB, PHBV, PBAT have also been reinforced with natural fibers. For example, PCL based composites with date palm [118,120] and hemp fiber [119] showed significant improvement in tensile and flexural strength, suggesting that the flexibility of PCL can be counterbalanced through the addition of stiffens fibrous reinforcements. Similarly, PBS composites with Curaua [121] and hemp fibers [122] showed improved mechanical performance and, especially for hemp fiber, good sustainability due to their biodegradation under enzymatic hydrolysis and soil burial conditions.
Particularly interesting are the results obtained on PHB and PHVB composites using pineapple leaf [81], sisal [123] and alpha fibers [124], where not only were tensile strength properties improved, but also good recyclability and degradability was observed when subjected to water absorption in distilled and sea water. On the contrary, PBAT based composites have been mainly developed for packaging application. For example, PBAT combined with hemp though solvent casting showed antioxidant and antimicrobial activity, confirming its potential use in active packaging [127]. On the other hand, PBAT reinforced with kenaf [128] or alternative [125,126,129] fibers, showed improved in mechanical performance and biodegradability, especially when compatibilizer were added.
The incorporation of agave fibers into Mater-Bi® matrix, processed by melt compounding and compression molding, resulted in composites with enhanced recyclability and compostability (see Figure 12) [130].

4.1.3. Cellulose and Derivatives

Following the analysis of agricultural and natural-fiber wastes, a more limited number of studies has investigated the use of cellulose and its derivatives as fillers in biodegradable matrices. Despite their smaller presence in the literature, these works demonstrate the strong potential of cellulose structures to produce mechanically reinforced and sustainable composites. The main formulations, processing routes, and applications are summarized in Table 8.
PLA-based composites containing cellulose nanocrystals (CNCs) or micro-fibrillated cellulose (MFC) exhibited significant improvements in mechanical strength elasticity, and shape-memory behavior. More in detail, PLA/CNC composites fabricated by 3D printing exhibited marked improvements in mechanical strength and shape-memory behavior (see Figure 13), confirming the effectiveness of cellulose nanocrystals as reinforcing and functional agents [133]. PLA/MFC films have been processed via film blowing, for flexible packaging applications, and enhanced mechanical properties compared with neat PLA were observed [136]. In addition, composites filled with nanocellulose from agricultural sources [137] displayed stable morphological structures and increased tensile strength and stiffness, confirming the efficiency of cellulose as a reinforcing agent. Similarly, Eucomis autumnalis cellulose has been incorporated into PLA by compression molding, obtaining composites with homogeneous filler dispersion and stable tensile performance that allow to produce good quality filament for 3D printing applications [134].
The introduction of lignin in PLA [135] produced composites with higher toughness and elongation at break ideal for biomedical applications. Additionally, waste-paper cellulose [138] was successfully used to obtain biocomposites with improved mechanical integrity and sustainability, demonstrating the potential of secondary cellulose streams.
The addition of agriculture waste derived cellulose to PCL led to the enhancement of mechanical properties of the materials [139,140,141]. When lignin is added to PBAT matrices, it enhanced the modulus while also promoting photo-degradability, a desirable property for packaging and outdoor exposure [142,143]. Coconut nanofibrils and potato-peel cellulose acetate incorporated into PVA-based systems enhanced mechanical properties and biodegradability, confirming the suitability of cellulose derivatives for single-use packaging [144,145].
Regarding the end of life, cellulose-reinforced systems generally exhibited accelerated disintegration under composting and soil-burial conditions [139,144]. The hydrophilic nature and high surface reactivity of cellulose promote hydrolytic and enzymatic degradation, enabling environmentally compatible disposal.

4.1.4. Alternative Organic Waste

Research has recently expanded toward the use of less conventional plant-derived wastes. These materials, often coming from marine or desert ecosystems, further expand the range of renewable resources that can be valorized in biodegradable polymer matrices. The main examples, together with processing methods, properties and related applications are summarized in Table 9.
Posidonia oceanica residues, available as leaves or fibrous balls, were typically incorporated into PLA or Mater-Bi® matrices by compression or injection molding, producing composites with good processability, improved ductility, and enhanced sustainability [146,147,150]. When used as a powder dispersed in PLA solution and processed via electrospinning [148], this filler allowed to generated highly porous structures with excellent mechanical strength, improved electrostatic attraction and filtration efficiency (see Figure 14a,b), producing a device suitable for air-purification applications.
Other natural sources, such as aloe vera [149] and microalgal biomass [151], were processed via injection molding or extrusion, exploiting the presence of bioactive compounds that act as natural plasticizers and photo-protective agents. Aloe vera based composites exhibited greater UV resistance and accelerated biodegradation under compost or soil conditions. From an end-of-life perspective, microalgal based composites demonstrated accelerated disintegration and biodegradation under composting or soil-burial conditions.
Similarly, moringa oleifera [152] and babassu [153] residues were combined with PBAT and PBAT/PHB matrices through wire-extension techniques, producing flexible and transparent films with improved mechanical and barrier properties while maintaining full biodegradability. These characteristics represent an appealing feature for food packaging and mulch films.
This confirms that even unconventional plant residues can be effectively used as active fillers in biodegradable polymers increasing their functional properties, without compromising their environmental performance.

4.2. Animal-Derived Organic Waste

In line with what has been observed for plant-derived fillers, animal-derived residues have also been successfully integrated into biodegradable polymer matrices to obtain sustainable and functional composites. The use of such fillers not only promotes the valorization of organic by-products from the fishery sectors but also enables the development of materials with unique combinations of mechanical and functional properties. The main examples, together with processing routes and applications, are reported in Table 10.
After the selection and processing of animal-derived fillers, biodegradable composites have been developed to evaluate their performance and application. In these systems, residues such as eggshell, marine shells, fish bones, gelatin, and wool waste were incorporated into different polymeric matrices using techniques including melt compounding, injection molding, compression molding, film blowing, and 3D printing.
More in detail, eggshell-based composites, prepared mainly through melt compounding and injection molding (see Figure 15a), generally show an increase in stiffness due to the high calcium carbonate content [154,155,156]. Shellfish-derived fillers, such as oyster or crab shells, also act as reinforcing agents, improving the mechanical properties and enhancing biodegradability of the resulting materials [81,158,159]. Fish-derived fillers, including bones and gelatin residues, provide protein- and mineral-rich phases that contribute to improved processability and mechanical properties [160] or barrier and antioxidant properties [157], which are particularly beneficial for packaging and food-contact applications.
Furthermore, wool waste powders, obtained from non-textile sheep breeds and incorporated in PLA solution, enabled the fabrication of fibrous Biocomposite membranes via solution blow spinning with excellent mechanical performance and air filtration efficiency (see Figure 15b), demonstrating their suitability for environmental remediation and air purification systems [161].
From an end-of-life perspective, most composites containing animal-derived fillers demonstrated enhanced biodegradation and disintegration rates, mainly due to the presence of mineral or protein-based components that facilitate hydrolytic and enzymatic degradation. Systems incorporating shell powders showed improved compostability and soil disintegration, as the calcium carbonate and chitin phases act as nucleating and hydrolysis-promoting agents [81,158]. Composites based on fish-derived fillers, such as gelatin, underwent accelerated degradation under composting conditions, confirming their potential for eco-friendly disposal [157].
Overall, composites reinforced with animal-derived organic waste exhibit enhanced mechanical, and functional properties, often accompanied by increased biodegradability and sustainability. These materials can be valorized for the production of advanced applications composites ranging from biomedical and packaging uses to air filtration and environmental protection, offering an effective strategy to valorize residues from the fishery and livestock sectors within a circular and low-impact materials framework.

5. Conclusions

The valorization of plant- and animal-derived organic waste as functional fillers in biodegradable polymeric matrices represents a consolidated and rapidly expanding research direction. The studies analyzed that waste materials (lignocellulosic residues, natural fibers, cellulose derivatives, or animal by-products) can significantly enhance the mechanical, thermal, functional, and biodegradation behavior of biocomposites, often enabling additional benefits such as antioxidant activity, barrier improvements, fertilizer release, or air-filtration performance. Across all polymer matrices, the effectiveness of these fillers is strongly governed by their intrinsic composition, morphology, and surface chemistry. Grinding, drying, sieving, chemical modification, and compatibilization play a central role in optimizing dispersion and interfacial adhesion. Moreover, the increasing integration of waste fillers into 3D printing and advanced processing technologies confirms their suitability for high-value and technologically relevant applications.
Despite these advances, several issues still require optimization: waste heterogeneity, limited standardization of treatments, and the need for more systematic correlations between filler characteristics and final properties. Future research should also integrate life-cycle assessments, scalability analyses, and industrial processing to fully exploit the potential of organic waste in biodegradable polymeric materials.
Overall, the current evidence highlights a transition toward more advanced and purposeful material design, in which organic waste is no longer a by-product but a strategic resource for developing high-performance biodegradable biocomposites.

Author Contributions

Conceptualization, R.S., F.P.L.M., G.L.R., V.T. and M.C.C.; methodology, R.S., F.P.L.M., G.L.R., V.T. and M.C.C.; software, M.C.C.; validation, R.S., F.P.L.M., G.L.R., V.T. and M.C.C.; resources, R.S.; writing—original draft preparation, V.T. and M.C.C.; writing—review and editing, R.S. and M.C.C.; visualization, V.T. and M.C.C.; supervision, R.S., F.P.L.M. and G.L.R.; project administration, R.S. and F.P.L.M.; funding acquisition, R.S. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Italian Ministry of Education, University and Research (MUR) under the PRIN 2022 - 20228WNZ2Z "Green composites based on biodegradable polymers and vegetal biomasses of Mediterranean area: processing, characterization and degradability", which is financed by the European Union.

Institutional Review Board Statement

Not applicable

Data Availability Statement

No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Williams, A.T.; Rangel-Buitrago, N. The Past, Present, and Future of Plastic Pollution. Mar. Pollut. Bull. 2022, 176, 113429. [Google Scholar] [CrossRef] [PubMed]
  2. Horton, A.A. Plastic Pollution: When Do We Know Enough? J. Hazard. Mater. 2022, 422, 126885. [Google Scholar] [CrossRef] [PubMed]
  3. Shams, M.; Alam, I.; Mahbub, M.S. Plastic Pollution during COVID-19: Plastic Waste Directives and Its Long-Term Impact on the Environment. Environ. Adv. 2021, 5, 100119. [Google Scholar] [CrossRef] [PubMed]
  4. Plastics the Fast Facts 2025 • Plastics Europe. Plast. Eur.
  5. Wu, F.; Misra, M.; Mohanty, A.K. Challenges and New Opportunities on Barrier Performance of Biodegradable Polymers for Sustainable Packaging. Prog. Polym. Sci. 2021, 117, 101395. [Google Scholar] [CrossRef]
  6. Dallaev, R.; Papež, N.; Allaham, M.M.; Holcman, V. Biodegradable Polymers: Properties, Applications, and Environmental Impact. Polymers 2025, 17, 1981. [Google Scholar] [CrossRef] [PubMed]
  7. Olonisakin, K.; Mohanty, A.K.; Thimmanagari, M.; Misra, M. Recent Advances in Biodegradable Polymer Blends and Their Biocomposites: A Comprehensive Review. Green Chem. 2025, 27, 11656–11704. [Google Scholar] [CrossRef]
  8. Latos-Brozio, M.; Rułka, K.; Masek, A. Review of Bio-Fillers Dedicated to Polymer Compositions. Chem. Biodivers. 2025, 22, e202500406. [Google Scholar] [CrossRef]
  9. Scaffaro, R.; Maio, A.; Gulino, E.F.; Megna, B. Structure-Property Relationship of PLA-Opuntia Ficus Indica Biocomposites. Compos. Part B Eng. 2019, 167, 199–206. [Google Scholar] [CrossRef]
  10. Scaffaro, R.; Maio, A.; Gulino, E.F.; Pitarresi, G. Lignocellulosic Fillers and Graphene Nanoplatelets as Hybrid Reinforcement for Polylactic Acid: Effect on Mechanical Properties and Degradability. Compos. Sci. Technol. 2020, 190, 108008. [Google Scholar] [CrossRef]
  11. Scaffaro, R.; Citarrella, M.C.; Morreale, M. Green Composites Based on Mater-Bi® and Solanum Lycopersicum Plant Waste for 3D Printing Applications. Polymers 2023, 15, 325. [Google Scholar] [CrossRef]
  12. Citarrella, M.C.; Scaffaro, R. Sustainable and Reusable 3D Fibrous Structures Based on PLA and Biomass Wastes for FOG (Fat, Oil, Greases) Wastewater Treatment. J. Environ. Chem. Eng. 2025, 13, 116349. [Google Scholar] [CrossRef]
  13. Maio, A.; Gulino, E.F.; Gammino, M.; Citarrella, M.C.; Scaffaro, R. Photochemical Degradation of PLA-Based Green Composites Containing Waste Biomass from Posidonia Oceanica, Chamaerops Humilis and Ailanthus Altissima: A Comparative Study. Polym. Degrad. Stab. 2025, 234, 111204. [Google Scholar] [CrossRef]
  14. Scaffaro, R.; Maio, A.; Gulino, E.F. Hydrolytic Degradation of PLA/Posidonia Oceanica Green Composites: A Simple Model Based on Starting Morpho-Chemical Properties. Compos. Sci. Technol. 2021, 213, 108930. [Google Scholar] [CrossRef]
  15. Antor, R.I.; Bithi, A.M.; Nahin, A.M. Variation in Mechanical Properties of Polymer Composites With Reinforcements From Different Animal Origins—A Comprehensive Review. Int. J. Polym. Sci. 2025, 2025, 4184239. [Google Scholar] [CrossRef]
  16. Sholokhova, A.; Varžinskas, V.; Rutkaitė, R. Valorization of Agro-Waste in Bio-Based and Biodegradable Polymer Composites: A Comprehensive Review with Emphasis on Europe Perspective. Waste Biomass Valorization 2025, 16, 1537–1571. [Google Scholar] [CrossRef]
  17. Tabassum, Z.; Girdhar, M.; Anand, A.; Kumari, N.; Sood, B.; Malik, T.; Kumar, A.; Mohan, A. Trash to Treasure: Advancing Resource Efficiency Using Waste-Derived Fillers as Sustainable Reinforcing Agents in Bioplastics. Mater. Adv. 2025, 6, 527–546. [Google Scholar] [CrossRef]
  18. Gupta, N.; Mahur, B.K.; Izrayeel, A.M.D.; Ahuja, A.; Rastogi, V.K. Biomass Conversion of Agricultural Waste Residues for Different Applications: A Comprehensive Review. Environ. Sci. Pollut. Res. 2022, 29, 73622–73647. [Google Scholar] [CrossRef] [PubMed]
  19. Akter, M.; Uddin, M.H.; Tania, I.S. Biocomposites Based on Natural Fibers and Polymers: A Review on Properties and Potential Applications. J. Reinf. Plast. Compos. 2022, 41, 705–742. [Google Scholar] [CrossRef]
  20. Farah, S.; Anderson, D.G.; Langer, R. Physical and Mechanical Properties of PLA, and Their Functions in Widespread Applications — A Comprehensive Review. Adv. Drug Deliv. Rev. 2016, 107, 367–392. [Google Scholar] [CrossRef] [PubMed]
  21. Polylactic Acid: Synthesis, Properties and Applications. In Monomers, Polymers and Composites from Renewable Resources; Elsevier, 2008; pp. 433–450.
  22. Södergård, A.; Stolt, M. Properties of Lactic Acid Based Polymers and Their Correlation with Composition. Prog. Polym. Sci. 2002, 27, 1123–1163. [Google Scholar] [CrossRef]
  23. Nofar, M.; Sacligil, D.; Carreau, P.J.; Kamal, M.R.; Heuzey, M.-C. Poly (Lactic Acid) Blends: Processing, Properties and Applications. Int. J. Biol. Macromol. 2019, 125, 307–360. [Google Scholar] [CrossRef] [PubMed]
  24. Lasprilla, A.J.R.; Martinez, G.A.R.; Lunelli, B.H.; Jardini, A.L.; Filho, R.M. Poly-Lactic Acid Synthesis for Application in Biomedical Devices — A Review. Biotechnol. Adv. 2012, 30, 321–328. [Google Scholar] [CrossRef] [PubMed]
  25. Singhvi, M.S.; Zinjarde, S.S.; Gokhale, D.V. Polylactic Acid: Synthesis and Biomedical Applications. J. Appl. Microbiol. 2019, 127, 1612–1626. [Google Scholar] [CrossRef] [PubMed]
  26. Sonchaeng, U.; Iñiguez-Franco, F.; Auras, R.; Selke, S.; Rubino, M.; Lim, L.-T. Poly(Lactic Acid) Mass Transfer Properties. Prog. Polym. Sci. 2018, 86, 85–121. [Google Scholar] [CrossRef]
  27. Coudane, J.; Nottelet, B.; Mouton, J.; Garric, X.; Van Den Berghe, H. Poly(ε-Caprolactone)-Based Graft Copolymers: Synthesis Methods and Applications in the Biomedical Field: A Review. Molecules 2022, 27, 7339. [Google Scholar] [CrossRef] [PubMed]
  28. Sachan, R.; Warkar, S.G.; Purwar, R. An Overview on Synthesis, Properties and Applications of Polycaprolactone Copolymers, Blends & Composites. Polym.-Plast. Technol. Mater. 2023, 62, 327–358. [Google Scholar] [CrossRef]
  29. Backes, E.H.; Harb, S.V.; Beatrice, C.A.G.; Shimomura, K.M.B.; Passador, F.R.; Costa, L.C.; Pessan, L.A. Polycaprolactone Usage in Additive Manufacturing Strategies for Tissue Engineering Applications: A Review. J. Biomed. Mater. Res. B Appl. Biomater. 2022, 110, 1479–1503. [Google Scholar] [CrossRef]
  30. Xu, J.; Guo, B.-H. Poly(Butylene Succinate) and Its Copolymers: Research, Development and Industrialization. Biotechnol. J. 2010, 5, 1149–1163. [Google Scholar] [CrossRef]
  31. Rafiqah, S.A.; Khalina, A.; Harmaen, A.S.; Tawakkal, I.A.; Zaman, K.; Asim, M.; Nurrazi, M.N.; Lee, C.H. A Review on Properties and Application of Bio-Based Poly(Butylene Succinate). Polymers 2021, 13, 1436. [Google Scholar] [CrossRef] [PubMed]
  32. Bi, S.; Tan, B.; Soule, J.L.; Sobkowicz, M.J. Enzymatic Degradation of Poly (Butylene Succinate-Co-Hexamethylene Succinate). Polym. Degrad. Stab. 2018, 155, 9–14. [Google Scholar] [CrossRef]
  33. Barletta, M.; Aversa, C.; Ayyoob, M.; Gisario, A.; Hamad, K.; Mehrpouya, M.; Vahabi, H. Poly(Butylene Succinate) (PBS): Materials, Processing, and Industrial Applications. Prog. Polym. Sci. 2022, 132, 101579. [Google Scholar] [CrossRef]
  34. Naser, A.Z.; Deiab, I.; Defersha, F.; Yang, S. Expanding Poly(Lactic Acid) (PLA) and Polyhydroxyalkanoates (PHAs) Applications: A Review on Modifications and Effects. Polymers 2021, 13, 4271. [Google Scholar] [CrossRef]
  35. Grigore, M.E.; Grigorescu, R.M.; Iancu, L.; Ion, R.-M.; Zaharia, C.; Andrei, E.R. Methods of Synthesis, Properties and Biomedical Applications of Polyhydroxyalkanoates: A Review. J. Biomater. Sci. Polym. Ed. 2019, 30, 695–712. [Google Scholar] [CrossRef]
  36. Lee, J.; Park, C.; Fai Tsang, Y.; Andrew Lin, K.-Y. Towards Sustainable Production of Polybutylene Adipate Terephthalate: Non-Biological Catalytic Syntheses of Biomass-Derived Constituents. ChemSusChem 2024, 17, e202401070. [Google Scholar] [CrossRef]
  37. Denial, Mahata; Karthikeyan, S.; Godse, R.; Gupta, V.K. Poly(Butylene Adipate-Co-Terephthalate) Polyester Synthesis Process and Product Development. Polym. Sci. Ser. C 2021, 63, 102–111. [Google Scholar] [CrossRef]
  38. Ferreira, F.V.; Cividanes, L.S.; Gouveia, R.F.; Lona, L.M.F. An Overview on Properties and Applications of Poly(Butylene Adipate-Co-Terephthalate)–PBAT Based Composites. Polym. Eng. Sci. 2019, 59, E7–E15. [Google Scholar] [CrossRef]
  39. Jian, J.; Xiangbin, Z.; Xianbo, H. An Overview on Synthesis, Properties and Applications of Poly(Butylene-Adipate-Co-Terephthalate)–PBAT. Adv. Ind. Eng. Polym. Res. 2020, 3, 19–26. [Google Scholar] [CrossRef]
  40. Pokhrel, S. A Review on Introduction and Applications of Starch and Its Biodegradable Polymers. Int. J. Environ. 2015, 4, 114–125. [Google Scholar] [CrossRef]
  41. Diyana, Z.N.; Jumaidin, R.; Selamat, M.Z.; Ghazali, I.; Julmohammad, N.; Huda, N.; Ilyas, R.A. Physical Properties of Thermoplastic Starch Derived from Natural Resources and Its Blends: A Review. Polymers 2021, 13, 1396. [Google Scholar] [CrossRef] [PubMed]
  42. Policastro, G.; Panico, A.; Fabbricino, M. Improving Biological Production of Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate) (PHBV) Co-Polymer: A Critical Review. Rev. Environ. Sci. Biotechnol. 2021, 20, 479–513. [Google Scholar] [CrossRef]
  43. Su, S.; Kopitzky, R.; Tolga, S.; Kabasci, S. Polylactide (PLA) and Its Blends with Poly(Butylene Succinate) (PBS): A Brief Review. Polymers 2019, 11, 1193. [Google Scholar] [CrossRef] [PubMed]
  44. Ahmed, R.; Manik, K.H.; Nath, A.; Shohag, J.R.; Mim, J.J.; Hossain, N. Recent Advances in Sustainable Natural Fiber Composites: Environmental Benefits, Applications, and Future Prospects. Mater. Today Sustain. 2025, 32, 101220. [Google Scholar] [CrossRef]
  45. Puttegowda, M. Eco-Friendly Composites: Exploring the Potential of Natural Fiber Reinforcement. Discov. Appl. Sci. 2025, 7, 401. [Google Scholar] [CrossRef]
  46. Avella, A.; Idström, A.; Mincheva, R.; Nakayama, K.; Evenäs, L.; Raquez, J.-M.; Lo Re, G. Reactive Melt Crosslinking of Cellulose Nanocrystals/Poly(ε-Caprolactone) for Heat-Shrinkable Network. Compos. Part Appl. Sci. Manuf. 2022, 163, 107166. [Google Scholar] [CrossRef]
  47. Avella, A.; Ruda, M.; Gioia, C.; Sessini, V.; Roulin, T.; Carrick, C.; Verendel, J.; Lo Re, G. Lignin Valorization in Thermoplastic Biomaterials: From Reactive Melt Processing to Recyclable and Biodegradable Packaging. Chem. Eng. J. 2023, 463, 142245. [Google Scholar] [CrossRef]
  48. Restaino, O.F.; Giosafatto, C.V.L.; Mirpoor, S.F.; Cammarota, M.; Hejazi, S.; Mariniello, L.; Schiraldi, C.; Porta, R. Sustainable Exploitation of Posidonia Oceanica Sea Balls (Egagropili): A Review. Int. J. Mol. Sci. 2023, 24, 7301. [Google Scholar] [CrossRef]
  49. Fragassa, C.; Pesic, A.; Mattiello, S.; Pavlovic, A.; Santulli, C. Exploring the Potential of Posidonia Oceanica Fibers in Eco-Friendly Composite Materials: A Review. J. Mar. Sci. Eng. 2025, 13, 177. [Google Scholar] [CrossRef]
  50. Chandrappa, D.R.K.; Kamath, M.S.S. The Egg Shell as a Filler in Composite Materials - a Review. J. Mech. Energy Eng. 2020, 4, 335–340. [Google Scholar] [CrossRef]
  51. Şen, İ.; Sever, K. Production and Characterization of Agricultural Waste Natural Fiber-Filled Polylactic Acid Composites. Polym. Bull. 2025, 82, 4051–4074. [Google Scholar] [CrossRef]
  52. Komal, U.K.; Lila, M.K.; Singh, I. PLA/Banana Fiber Based Sustainable Biocomposites: A Manufacturing Perspective. Compos. Part B Eng. 2020, 180, 107535. [Google Scholar] [CrossRef]
  53. Fico, D.; Rizzo, D.; De Carolis, V.; Esposito Corcione, C. Bio-Composite Filaments Based on Poly(Lactic Acid) and Cocoa Bean Shell Waste for Fused Filament Fabrication (FFF): Production, Characterization and 3D Printing. Materials 2024, 17, 1260. [Google Scholar] [CrossRef]
  54. Almeida, V.H.M. de; Jesus, R.M. de; Santana, G.M.; Khan, S.; Silva, E.F.M.S.; Cruz, I.S. da; Santos, I. de S.; dos Anjos, P.N.M. The Development of Biocomposite Filaments for 3D Printing by Utilizing a Polylactic Acid (PLA) Polymer Matrix Reinforced with Cocoa Husk Cellulose Fibers. Polymers 2024, 16, 1757. [Google Scholar] [CrossRef]
  55. Bruna, J.E.; Castillo, M.; López de Dicastillo, C.; Muñoz-Shugulí, C.; Lira, M.; Guarda, A.; Rodríguez-Mercado, F.J.; Galotto, M.J. Development of Active Biocomposite Films Based on Poly(Lactic Acid) and Wine by-Product: Effect of Grape Pomace Content and Extrusion Temperature. J. Appl. Polym. Sci. 2023, 140, e54425. [Google Scholar] [CrossRef]
  56. Aliotta, L.; Vannozzi, A.; Bonacchi, D.; Coltelli, M.-B.; Lazzeri, A. Analysis, Development, and Scaling-Up of Poly(Lactic Acid) (PLA) Biocomposites with Hazelnuts Shell Powder (HSP). Polymers 2021, 13, 4080. [Google Scholar] [CrossRef] [PubMed]
  57. Balart, J. f.; García-Sanoguera, D.; Balart, R.; Boronat, T.; Sánchez-Nacher, L. Manufacturing and Properties of Biobased Thermoplastic Composites from Poly(Lactid Acid) and Hazelnut Shell Wastes. Polym. Compos. 2018, 39, 848–857. [Google Scholar] [CrossRef]
  58. Scaffaro, R.; Gulino, E.F.; Citarrella, M.C.; Maio, A. Green Composites Based on Hedysarum Coronarium with Outstanding FDM Printability and Mechanical Performance. Polymers 2022, 14, 1198. [Google Scholar] [CrossRef]
  59. Lima, E.M.B.; Middea, A.; Neumann, R.; Thiré, R.M. da S.M.; Pereira, J.F.; de Freitas, S.C.; Penteado, M.S.; Lima, A.M.; Minguita, A.P. da S.; Mattos, M. da C.; et al. Biocomposites of PLA and Mango Seed Waste: Potential Material for Food Packaging and a Technological Alternative to Reduce Environmental Impact. Starch - Stärke 2021, 73, 2000118. [Google Scholar] [CrossRef]
  60. Fico, D.; Rizzo, D.; De Carolis, V.; Montagna, F.; Palumbo, E.; Corcione, C.E. Development and Characterization of Sustainable PLA/Olive Wood Waste Composites for Rehabilitation Applications Using Fused Filament Fabrication (FFF). J. Build. Eng. 2022, 56, 104673. [Google Scholar] [CrossRef]
  61. Scaffaro, R.; Maio, A.; Gulino, E.F.; Alaimo, G.; Morreale, M. Green Composites Based on PLA and Agricultural or Marine Waste Prepared by FDM. Polymers 2021, 13, 1361. [Google Scholar] [CrossRef] [PubMed]
  62. Botta, L.; Mistretta, M.C.; Lamattina, G.; Gargano, F.; Liguori, G. Opuntia Ficus-Indica Fruit by-Products as Fillers for PLA-Based Biocomposites: A Comparison between Glochids and Peel. Polym. Compos. 2025, 46, 12243–12256. [Google Scholar] [CrossRef]
  63. Sambudi, N.S.; Lin, W.Y.; Harun, N.Y.; Mutiari, D. Modification of Poly(Lactic Acid) with Orange Peel Powder as Biodegradable Composite. Polymers 2022, 14, 4126. [Google Scholar] [CrossRef]
  64. Wu, C.-S.; Tsou, C.-H. Fabrication, Characterization, and Application of Biocomposites from Poly(Lactic Acid) with Renewable Rice Husk as Reinforcement. J. Polym. Res. 2019, 26, 44. [Google Scholar] [CrossRef]
  65. Sun, Y.; Wang, Y.; Mu, W.; Zheng, Z.; Yang, B.; Wang, J.; Zhang, R.; Zhou, K.; Chen, L.; Ying, J.; et al. Mechanical Properties of 3D Printed Micro-Nano Rice Husk/Polylactic Acid Filaments. J. Appl. Polym. Sci. 2022, 139, e52619. [Google Scholar] [CrossRef]
  66. Asheghi-Oskooee, R.; Morsali, P.; Mohammadi-Roshandeh, J.; Hemmati, F. Tailoring Interfacial Adhesion and Mechanical Performance of Biocomposites Based on Poly(Lactic Acid)/Rice Straw by Using Maleic Anhydride through Reactive Extrusion Process. J. Appl. Polym. Sci. 2024, 141, e55153. [Google Scholar] [CrossRef]
  67. Kampeerapappun, P.; O-Charoen, N.; Dhamvithee, P.; Jansri, E. Biocomposite Based on Polylactic Acid and Rice Straw for Food Packaging Products. Polymers 2024, 16, 1038. [Google Scholar] [CrossRef] [PubMed]
  68. Yu, W.; Dong, L.; Lei, W.; Shi, J. Rice Straw Powder/Polylactic Acid Biocomposites for Three-Dimensional Printing. Adv. Compos. Lett. 2020, 29, 2633366X20967360. [Google Scholar] [CrossRef]
  69. Ramesh, T.; Saravanakumar, S.S.; Balavairavan, B.; Senthamaraikannan, P. Development and Characterization of a Polylactic Acid/Sesame Husk Powder–Based Biocomposite Film for Packaging Application. Waste Biomass Valorization 2024, 15, 2845–2856. [Google Scholar] [CrossRef]
  70. Gomez-Caturla, J.; Montanes, N.; Quiles-Carrillo, L.; Balart, R.; Garcia-Garcia, D.; Dominici, F.; Puglia, D.; Torre, L. Development of Biodegradable PLA Composites and Tangerine Peel Flour with Improved Toughness Containing a Natural-Based Terpenoid. Express Polym. Lett. 2023, 17, 789–805. [Google Scholar] [CrossRef]
  71. Kocak, E.; Cetin, M.S.; Kizilirmak Esmer, O.; Karahan Toprakci, H.A. Effects of Tomato Peel Extract on Morphological, Chemical, Thermal, and Mechanical Properties of Poly(Lactic Acid). Iran. Polym. J. 2023, 32, 1135–1148. [Google Scholar] [CrossRef]
  72. Giani, N.; Maccaferri, E.; Benelli, T.; Bovo, M.; Torreggiani, D.; Campari, E.G.; Tassinari, P.; Giorgini, L.; Mazzocchetti, L. Valorization of Agro-Wastes as Fillers in PLA-Based Biocomposites for Increasing Sustainability in Fused Deposition Modeling Additive Manufacturing. Materials 2024, 17, 1421. [Google Scholar] [CrossRef] [PubMed]
  73. Giani, N.; Mazzocchetti, L.; Benelli, T.; Bovo, M.; Gazzotti, S.; Torreggiani, D.; Tassinari, P.; Giorgini, L. A New Biocomposite Material Based on Wheat Waste and Suitable for 3D Printing Applications. Macromol. Symp. 2022, 405, 2100235. [Google Scholar] [CrossRef]
  74. Hejna, A.; Sulyman, M.; Przybysz, M.; Saeb, M.R.; Klein, M.; Formela, K. On the Correlation of Lignocellulosic Filler Composition with the Performance Properties of Poly(ε-Caprolactone) Based Biocomposites. Waste Biomass Valorization 2020, 11, 1467–1479. [Google Scholar] [CrossRef]
  75. De Monte, C.; Arrighetti, L.; Ricci, L.; Civello, A.; Bronco, S. Agro-Waste Bean Fibers as Reinforce Materials for Polycaprolactone Composites. Compounds 2023, 3, 504–520. [Google Scholar] [CrossRef]
  76. Picard, M.C.; Rodriguez-Uribe, A.; Thimmanagari, M.; Misra, M.; Mohanty, A.K. Sustainable Biocomposites from Poly(Butylene Succinate) and Apple Pomace: A Study on Compatibilization Performance. Waste Biomass Valorization 2020, 11, 3775–3787. [Google Scholar] [CrossRef]
  77. Araújo, R.P.; Beatrice, C.A.G.; Backes, E.H.; Costa, L.C. Enhancing Sustainability and Biodegradability of Poly(Butylene Succinate) (PBS) Composite Filaments Reinforced with Cocoa Bean Shell Residues. Polym. Compos. 2024, 45, 13650–13662. [Google Scholar] [CrossRef]
  78. Liminana, P.; Garcia-Sanoguera, D.; Quiles-Carrillo, L.; Balart, R.; Montanes, N. Development and Characterization of Environmentally Friendly Composites from Poly(Butylene Succinate) (PBS) and Almond Shell Flour with Different Compatibilizers. Compos. Part B Eng. 2018, 144, 153–162. [Google Scholar] [CrossRef]
  79. Sasimowski, E.; Grochowicz, M.; Szajnecki, Ł. Preparation and Spectroscopic, Thermal, and Mechanical Characterization of Biocomposites of Poly(Butylene Succinate) and Onion Peels or Durum Wheat Bran. Materials 2023, 16, 6799. [Google Scholar] [CrossRef] [PubMed]
  80. Root, K.P.; Pal, A.K.; Pesaranhajiabbas, E.; Mohanty, A.K.; Misra, M. Injection Moulded Composites from High Biomass Filled Biodegradable Plastic: Properties and Performance Evaluation for Single-Use Applications. Compos. Part C Open Access 2023, 11, 100358. [Google Scholar] [CrossRef]
  81. Wu, C.-S.; Wu, D.-Y.; Wang, S.-S. Preparation, Characterization, and Functionality of Bio-Based Polyhydroxyalkanoate and Renewable Natural Fiber with Waste Oyster Shell Composites. Polym. Bull. 2021, 78, 4817–4834. [Google Scholar] [CrossRef]
  82. Wu, C.-S. Preparation and Characterization of Polyhydroxyalkanoate Bioplastic-Based Green Renewable Composites from Rice Husk. J. Polym. Environ. 2014, 22, 384–392. [Google Scholar] [CrossRef]
  83. Sánchez-Safont, E.L.; Aldureid, A.; Lagarón, J.M.; Gámez-Pérez, J.; Cabedo, L. Biocomposites of Different Lignocellulosic Wastes for Sustainable Food Packaging Applications. Compos. Part B Eng. 2018, 145, 215–225. [Google Scholar] [CrossRef]
  84. Batista, K.C.; Silva, D.A.K.; Coelho, L.A.F.; Pezzin, S.H.; Pezzin, A.P.T. Soil Biodegradation of PHBV/Peach Palm Particles Biocomposites. J. Polym. Environ. 2010, 18, 346–354. [Google Scholar] [CrossRef]
  85. Xu, Z.; Qiao, X.; Sun, K. Environmental-Friendly Corn Stover/Poly(Butylene Adipate-Co-Terephthalate) Biocomposites. Mater. Today Commun. 2020, 25, 101541. [Google Scholar] [CrossRef]
  86. Techawinyutham, L.; Techawinyutham, W.; Rangappa, S.M.; Siengchin, S. Lignocellulose Based Biofiller Reinforced Biopolymer Composites from Fruit Peel Wastes as Natural Pigment. Int. J. Biol. Macromol. 2024, 257, 128767. [Google Scholar] [CrossRef]
  87. Li, R.; Zhu, X.; Peng, F.; Lu, F. Biodegradable, Colorless, and Odorless PLA/PBAT Bioplastics Incorporated with Corn Stover. ACS Sustain. Chem. Eng. 2023, 11, 8870–8883. [Google Scholar] [CrossRef]
  88. Ibáñez García, A.; Martínez García, A.; Ferrándiz Bou, S. Study of the Influence of the Almond Shell Variety on the Mechanical Properties of Starch-Based Polymer Biocomposites. Polymers 2020, 12, 2049. [Google Scholar] [CrossRef]
  89. Ibáñez-García, A.; Martínez-García, A.; Ferrándiz-Bou, S. Influence of Almond Shell Content and Particle Size on Mechanical Properties of Starch-Based Biocomposites. Waste Biomass Valorization 2021, 12, 5823–5836. [Google Scholar] [CrossRef]
  90. Titone, V.; Rapisarda, M.; Pulvirenti, L.; Napoli, E.; Impallomeni, G.; Botta, L.; Mistretta, M.C.; Rizzarelli, P. Sustainable Biocomposites Based on Mater-Bi and Grape Pomace for a Circular Economy: Performance Evaluation and Degradation in Soil. Polym. Degrad. Stab. 2025, 231, 111091. [Google Scholar] [CrossRef]
  91. Ceraulo, M.; La Mantia, F.P.; Mistretta, M.C.; Titone, V. The Use of Waste Hazelnut Shells as a Reinforcement in the Development of Green Biocomposites. Polymers 2022, 14, 2151. [Google Scholar] [CrossRef] [PubMed]
  92. Scaffaro, R.; Citarrella, M.C.; Gulino, E.F.; Morreale, M. Hedysarum Coronarium-Based Green Composites Prepared by Compression Molding and Fused Deposition Modeling. Materials 2022, 15, 465. [Google Scholar] [CrossRef]
  93. Scaffaro, R.; Citarrella, M.C.; Gulino, E.F. Opuntia Ficus Indica Based Green Composites for NPK Fertilizer Controlled Release Produced by Compression Molding and Fused Deposition Modeling. Compos. Part Appl. Sci. Manuf. 2022, 159, 107030. [Google Scholar] [CrossRef]
  94. Scaffaro, R.; Gulino, E.F.; Citarrella, M.C. Multifunctional 3D-Printed Composites Based on Biopolymeric Matrices and Tomato Plant (Solanum Lycopersicum) Waste for Contextual Fertilizer Release and Cu(II) Ions Removal. Adv. Compos. Hybrid Mater. 2024, 7, 95. [Google Scholar] [CrossRef]
  95. Ramos, M.; Dominici, F.; Luzi, F.; Jiménez, A.; Garrigós, M.C.; Torre, L.; Puglia, D. Effect of Almond Shell Waste on Physicochemical Properties of Polyester-Based Biocomposites. Polymers 2020, 12, 835. [Google Scholar] [CrossRef] [PubMed]
  96. Wang, H.; Hassan, E.A.M.; Memon, H.; Elagib, T.H.H.; Abad AllaIdris, F. Characterization of Natural Composites Fabricated from Abutilon-Fiber-Reinforced Poly (Lactic Acid). Processes 2019, 7, 583. [Google Scholar] [CrossRef]
  97. Figueroa-Velarde, V.; Diaz-Vidal, T.; Cisneros-López, E.O.; Robledo-Ortiz, J.R.; López-Naranjo, E.J.; Ortega-Gudiño, P.; Rosales-Rivera, L.C. Mechanical and Physicochemical Properties of 3D-Printed Agave Fibers/Poly(Lactic) Acid Biocomposites. Materials 2021, 14, 3111. [Google Scholar] [CrossRef] [PubMed]
  98. Rao, G.S.; Debnath, K.; Mahapatra, R.N. Mechanical, Thermal, Morphological, and Fibre Characteristics During Injection Moulding of Green Composites. Fibers Polym. 2024, 25, 331–346. [Google Scholar] [CrossRef]
  99. Rao, G.S.; Debnath, K.; Mahapatra, R.N. Recycling and Degradation Behaviour of the Bamboo Fibre Reinforced Green Composite Fabricated by Injection Moulding. Sustain. Mater. Technol. 2024, 39, e00865. [Google Scholar] [CrossRef]
  100. Łączny, D.; Macko, M.; Moraczewski, K.; Szczepański, Z.; Trafarski, A. Influence of the Size of the Fiber Filler of Corn Stalks in the Polylactide Matrix Composite on the Mechanical and Thermomechanical Properties. Materials 2021, 14, 7281. [Google Scholar] [CrossRef]
  101. Gunti, R.; Ratna Prasad, A. v.; Gupta, A. v. s. s. k. s. Mechanical and Degradation Properties of Natural Fiber-Reinforced PLA Composites: Jute, Sisal, and Elephant Grass. Polym. Compos. 2018, 39, 1125–1136. [Google Scholar] [CrossRef]
  102. Le Duigou, A.; Barbé, A.; Guillou, E.; Castro, M. 3D Printing of Continuous Flax Fibre Reinforced Biocomposites for Structural Applications. Mater. Des. 2019, 180, 107884. [Google Scholar] [CrossRef]
  103. Morreale, M.; Mistretta, M.C.; Fiore, V. Creep Behavior of Poly(Lactic Acid) Based Biocomposites. Materials 2017, 10, 395. [Google Scholar] [CrossRef]
  104. Lang, M.; Neitzel, B.; MohammadKarimi, S.; Puch, F. Investigation on the Influence of Process Parameters on the Mechanical Properties of Extruded Bio-Based and Biodegradable Continuous Fiber-Reinforced Thermoplastic Sheets. Polymers 2023, 15, 3830. [Google Scholar] [CrossRef]
  105. Depuydt, D.; Balthazar, M.; Hendrickx, K.; Six, W.; Ferraris, E.; Desplentere, F.; Ivens, J.; Van Vuure, A.W. Production and Characterization of Bamboo and Flax Fiber Reinforced Polylactic Acid Filaments for Fused Deposition Modeling (FDM). Polym. Compos. 2019, 40, 1951–1963. [Google Scholar] [CrossRef]
  106. Vitiello, L.; Carroccio, S.C.; Ambrogi, V.; Podda, E.; Filippone, G.; Salzano de Luna, M. Degradation Kinetics of PLA/Hemp Biocomposites: Tradeoff between Nucleating Action and pro-Hydrolytic Effect of Natural Fibers. Compos. Sci. Technol. 2024, 257, 110806. [Google Scholar] [CrossRef]
  107. Pokhriyal, M.; Rakesh, P.K. Processing and Characterization of Novel Himalayacalamus Falconeri Fiber Reinforced Biodegradable Composites. Biomass Convers. Biorefinery 2024, 14, 21245–21260. [Google Scholar] [CrossRef]
  108. Shahar, F.S.; Hameed Sultan, M.T.; Safri, S.N.A.; Jawaid, M.; Abu Talib, Abd.R.; Basri, A.A.; Md Shah, A.U. Fatigue and Impact Properties of 3D Printed PLA Reinforced with Kenaf Particles. J. Mater. Res. Technol. 2022, 16, 461–470. [Google Scholar] [CrossRef]
  109. Yussuf, A.A.; Massoumi, I.; Hassan, A. Comparison of Polylactic Acid/Kenaf and Polylactic Acid/Rise Husk Composites: The Influence of the Natural Fibers on the Mechanical, Thermal and Biodegradability Properties. J. Polym. Environ. 2010, 18, 422–429. [Google Scholar] [CrossRef]
  110. Chung, T.-J.; Park, J.-W.; Lee, H.-J.; Kwon, H.-J.; Kim, H.-J.; Lee, Y.-K.; Tai Yin Tze, W. The Improvement of Mechanical Properties, Thermal Stability, and Water Absorption Resistance of an Eco-Friendly PLA/Kenaf Biocomposite Using Acetylation. Appl. Sci. 2018, 8, 376. [Google Scholar] [CrossRef]
  111. ’Atiqah Abdul Azam, F.; Tharazi, I.; Bakar Sulong, A.; Che Omar, R.; Muhamad, N. Mechanical Durability and Degradation Characteristics of Long Kenaf-Reinforced PLA Composites Fabricated Using an Eco-Friendly Method. Eng. Sci. Technol. Int. J. 2024, 57, 101820. [Google Scholar] [CrossRef]
  112. Nor, M.A.M.; Sapuan, S.M.; Yusoff, M.Z.M.; Zainudin, E.S. Mechanical, Thermal and Morphological Properties of Woven Kenaf Fiber Reinforced Polylactic Acid (PLA) Composites. Fibers Polym. 2022, 23, 2875–2884. [Google Scholar] [CrossRef]
  113. Cabrera-García, P.; Marrero, M.D.; Benítez, A.N. Disintegration and Marine Biodegradability of Biocomposite Using Pennisetum Setaceum Fiber and PLA as Matrix. Polym. Degrad. Stab. 2024, 230, 111026. [Google Scholar] [CrossRef]
  114. Kumar, K.S.; Gairola, S.; Singh, I. Sustainable Polymers and Sisal Fibers Based Green Composites: A Detailed Characterization and Analysis. Express Polym. Lett. 2023, 17, 992–1006. [Google Scholar] [CrossRef]
  115. Chaitanya, S.; Singh, I. Processing of PLA/Sisal Fiber Biocomposites Using Direct- and Extrusion-Injection Molding. Mater. Manuf. Process. 2017, 32, 468–474. [Google Scholar] [CrossRef]
  116. Samouh, Z.; Molnar, K.; Boussu, F.; Cherkaoui, O.; El Moznine, R. Mechanical and Thermal Characterization of Sisal Fiber Reinforced Polylactic Acid Composites. Polym. Adv. Technol. 2019, 30, 529–537. [Google Scholar] [CrossRef]
  117. Samouh, Z.; Molnár, K.; Hajba, S.; Boussu, F.; Cherkaoui, O.; El Moznine, R. Elaboration and Characterization of Biocomposite Based on Polylactic Acid and Moroccan Sisal Fiber as Reinforcement. Polym. Compos. 2021, 42, 3812–3826. [Google Scholar] [CrossRef]
  118. Saifullah, A.; Chacko, N.G.; Dhakal, H.N.; Khan, S.H.; Sarker, F.; Zhang, Z. Valorisation of Agricultural Residue Bio-Mass Date Palm Fibre in Dry-Blended Polycaprolactone (PCL) Bio-Composites for Sustainable Packaging Applications. Waste Biomass Valorization 2024, 15, 5805–5817. [Google Scholar] [CrossRef]
  119. Dhakal, H.N.; Ismail, S.O.; Zhang, Z.; Barber, A.; Welsh, E.; Maigret, J.-E.; Beaugrand, J. Development of Sustainable Biodegradable Lignocellulosic Hemp Fiber/Polycaprolactone Biocomposites for Light Weight Applications. Compos. Part Appl. Sci. Manuf. 2018, 113, 350–358. [Google Scholar] [CrossRef]
  120. Dhakal, H.; Bourmaud, A.; Berzin, F.; Almansour, F.; Zhang, Z.; Shah, D.U.; Beaugrand, J. Mechanical Properties of Leaf Sheath Date Palm Fibre Waste Biomass Reinforced Polycaprolactone (PCL) Biocomposites. Ind. Crops Prod. 2018, 126, 394–402. [Google Scholar] [CrossRef]
  121. Frollini, E.; Bartolucci, N.; Sisti, L.; Celli, A. Biocomposites Based on Poly(Butylene Succinate) and Curaua: Mechanical and Morphological Properties. Polym. Test. 2015, 45, 168–173. [Google Scholar] [CrossRef]
  122. Terzopoulou, Z.N.; Papageorgiou, G.Z.; Papadopoulou, E.; Athanassiadou, E.; Reinders, M.; Bikiaris, D.N. Development and Study of Fully Biodegradable Composite Materials Based on Poly(Butylene Succinate) and Hemp Fibers or Hemp Shives. Polym. Compos. 2016, 37, 407–421. [Google Scholar] [CrossRef]
  123. Lagazzo, A.; Moliner, C.; Bosio, B.; Botter, R.; Arato, E. Evaluation of the Mechanical and Thermal Properties Decay of PHBV/Sisal and PLA/Sisal Biocomposites at Different Recycle Steps. Polymers 2019, 11, 1477. [Google Scholar] [CrossRef]
  124. Hammiche, D.; Boukerrou, A.; Grohens, Y.; Guermazi, N.; Arrakhiz, F.E. Mechanical Properties and Biodegradation of Biocomposites Based on Poly (Hydroxybutyrate-Co-Valerate) and Alfa Fibers. J. Polym. Res. 2020, 27, 308. [Google Scholar] [CrossRef]
  125. Ferreira, F.V.; Pinheiro, I.F.; Mariano, M.; Cividanes, L.S.; Costa, J.C.M.; Nascimento, N.R.; Kimura, S.P.R.; Neto, J.C.M.; Lona, L.M.F. Environmentally Friendly Polymer Composites Based on PBAT Reinforced with Natural Fibers from the Amazon Forest. Polym. Compos. 2019, 40, 3351–3360. [Google Scholar] [CrossRef]
  126. Lamsaf, H.; Singh, S.; Pereira, J.; Poças, F. Multifunctional Properties of PBAT with Hemp (Cannabis Sativa) Micronised Fibres for Food Packaging: Cast Films and Coated Paper. Coatings 2023, 13, 1195. [Google Scholar] [CrossRef]
  127. Zeng, D.; Zhang, L.; Jin, S.; Zhang, Y.; Xu, C.; Zhou, K.; Lu, W. Mechanical Properties and Tensile Model of Hemp-Fiber-Reinforced Poly(Butylene Adipate-Co-Terephthalate) Composite. Materials 2022, 15, 2445. [Google Scholar] [CrossRef]
  128. Jeon, S.M.; Choo, J.E.; Park, T.H.; Hwang, S.W. The Effect of Isocyanate on the Properties of Poly(Butylene Adipate-Co-Terephthalate)/Kenaf Fiber Composites. Polym. Compos. 2024, 45, 10799–10811. [Google Scholar] [CrossRef]
  129. Badouard, C.; Traon, F.; Denoual, C.; Mayer-Laigle, C.; Paës, G.; Bourmaud, A. Exploring Mechanical Properties of Fully Compostable Flax Reinforced Composite Filaments for 3D Printing Applications. Ind. Crops Prod. 2019, 135, 246–250. [Google Scholar] [CrossRef]
  130. Pérez-Fonseca, A.A.; Reynoso-Llamas, C.; Robledo-Ortíz, J.R.; Rodrigue, D.; Martín del Campo, A.S. Recycling of Biodegradable Biobased Polymer/Agave Fiber Biocomposites. Polym. Compos. 2025, 46, 4059–4074. [Google Scholar] [CrossRef]
  131. Ghafari, R.; Scaffaro, R.; Maio, A.; Gulino, E.F.; Lo Re, G.; Jonoobi, M. Processing-Structure-Property Relationships of Electrospun PLA-PEO Membranes Reinforced with Enzymatic Cellulose Nanofibers. Polym. Test. 2020, 81, 106182. [Google Scholar] [CrossRef]
  132. Sessini, V.; Latty, H.; Milazzo, M.; Mirkhalaf, M.; Lo Re, G. Experiments and Computational Modelling Combined to Shed Light on the Reinforcement Mechanism in Reactive Extruded Pulp Fibres/Starch Biocomposites. Adv. Compos. Hybrid Mater. 2025, 8, 365. [Google Scholar] [CrossRef]
  133. Agbakoba, V.C.; Hlangothi, P.; Andrew, J.; John, M.J. Mechanical and Shape Memory Properties of 3D-Printed Cellulose Nanocrystal (CNC)-Reinforced Polylactic Acid Bionanocomposites for Potential 4D Applications. Sustainability 2022, 14, 12759. [Google Scholar] [CrossRef]
  134. Sikhosana, S.T.; Gumede, T.P.; Malebo, N.J.; Ogundeji, A.O.; Motloung, B. The Influence of Cellulose Content on the Morphology, Thermal, and Mechanical Properties of Poly(Lactic Acid)/Eucomis Autumnalis Cellulose Biocomposites. Polym. Eng. Sci. 2023, 63, 1411–1422. [Google Scholar] [CrossRef]
  135. Ren, Z.; Zhou, X.; Ding, K.; Ji, T.; Sun, H.; Chi, X.; Wei, Y.; Xu, M.; Cai, L.; Xia, C. Design of Sustainable 3D Printable Polylactic Acid Composites with High Lignin Content. Int. J. Biol. Macromol. 2023, 253, 127264. [Google Scholar] [CrossRef]
  136. Aliotta, L.; Gigante, V.; Garofalo, G.; Baiamonte, M.; Molinari, G.; Lazzeri, A.; La Mantia, F.P.; Botta, L. Poly(Lactic Acid) (PLA)/Micro-Fibrillated Cellulose (MFC) Biocomposites for Film Blowing Applications. Cellulose 2025, 32, 965–981. [Google Scholar] [CrossRef]
  137. de Souza, A.G.; Barbosa, R.F.S.; Rosa, D.S. Nanocellulose from Industrial and Agricultural Waste for Further Use in PLA Composites. J. Polym. Environ. 2020, 28, 1851–1868. [Google Scholar] [CrossRef]
  138. Delgado-Orti, C.; Navas-Martos, F.J.; Rodríguez-Liébana, J.A.; La Rubia, M.D.; Jurado-Contreras, S. Development of PLA–Waste Paper Biocomposites with High Cellulose Content. Polymers 2024, 16, 2000. [Google Scholar] [CrossRef] [PubMed]
  139. Yong, W.S.; Yeu, Y.L.; Chung, P.P.; Soon, K.H. Extraction and Characterization of Microcrystalline Cellulose (MCC) from Durian Rind for Biocomposite Application. J. Polym. Environ. 2024, 32, 6544–6575. [Google Scholar] [CrossRef]
  140. Chen, J.; Huang, Y.; Deng, L.; Jiang, H.; Yang, Z.; Yang, R.; Wu, D. Preparation and Research of PCL/Cellulose Composites: Cellulose Derived from Agricultural Wastes. Int. J. Biol. Macromol. 2023, 235, 123785. [Google Scholar] [CrossRef] [PubMed]
  141. Siqueira, G.; Bras, J.; Follain, N.; Belbekhouche, S.; Marais, S.; Dufresne, A. Thermal and Mechanical Properties of Bio-Nanocomposites Reinforced by Luffa Cylindrica Cellulose Nanocrystals. Carbohydr. Polym. 2013, 91, 711–717. [Google Scholar] [CrossRef]
  142. Botta, L.; Titone, V.; Teresi, R.; Scarlata, M.C.; Lo Re, G.; La Mantia, F.P.; Lopresti, F. Biocomposite PBAT/Lignin Blown Films with Enhanced Photo-Stability. Int. J. Biol. Macromol. 2022, 217, 161–170. [Google Scholar] [CrossRef]
  143. Botta, L.; Titone, V.; Mistretta, M.C.; La Mantia, F.P.; Modica, A.; Bruno, M.; Sottile, F.; Lopresti, F. PBAT Based Composites Reinforced with Microcrystalline Cellulose Obtained from Softwood Almond Shells. Polymers 2021, 13, 2643. [Google Scholar] [CrossRef]
  144. Taha, R.H.; Taha, T.H.; Elnouby, M.; Desouky, E.A.E.; Alhudhaibi, A.M.; Moustafa, M.; Elsherif, M.A.; Yahia, M.; Abu-Saied, M.A. Environmentally Green Film Blends: Polyvinyl Alcohol (PVA)/Cellulose Acetate (CA)/Potato Peel Starch as an Alternative to Petroleum Plastics. Cellulose 2024, 31, 6155–6172. [Google Scholar] [CrossRef]
  145. Camarena-Bononad, P.; Freitas, P.A.V.; Chiralt, A.; Vargas, M. Use of Cellulose Fibres from Posidonia Oceanica to Obtain Chitosan Biocomposites and Poly(Lactic Acid) Laminates. Polysaccharides 2025, 6, 27. [Google Scholar] [CrossRef]
  146. Scaffaro, R.; Lopresti, F.; Botta, L. PLA Based Biocomposites Reinforced with Posidonia Oceanica Leaves. Compos. Part B Eng. 2018, 139, 1–11. [Google Scholar] [CrossRef]
  147. Barandiaran, A.; Lascano, D.; Montanes, N.; Balart, R.; Selles, M.A.; Moreno, V. Improvement of the Ductility of Environmentally Friendly Poly(Lactide) Composites with Posidonia Oceanica Wastes Plasticized with an Ester of Cinnamic Acid. Polymers 2023, 15, 4534. [Google Scholar] [CrossRef] [PubMed]
  148. Scaffaro, R.; Citarrella, M.C. Stable and Reusable Electrospun Bio-Composite Fibrous Membranes Based on PLA and Natural Fillers for Air Filtration Applications. Sustain. Mater. Technol. 2024, 42, e01146. [Google Scholar] [CrossRef]
  149. Nicácio, P.; Albuquerque, A.; Dantas, L.; Siqueira, D.; Ries, A.; Wellen, R. Biocomposites Based on Poly(Lactic Acid)/Aloe Vera/Priplast. Effects of UVA Radiation on the Crystallization. Polym. Adv. Technol. 2023, 34, 3097–3110. [Google Scholar] [CrossRef]
  150. Scaffaro, R.; Maio, A.; Lopresti, F. Physical Properties of Green Composites Based on Poly-Lactic Acid or Mater-Bi® Filled with Posidonia Oceanica Leaves. Compos. Part Appl. Sci. Manuf. 2018, 112, 315–327. [Google Scholar] [CrossRef]
  151. Kalita, N.K.; Damare, N.A.; Hazarika, D.; Bhagabati, P.; Kalamdhad, A.; Katiyar, V. Biodegradation and Characterization Study of Compostable PLA Bioplastic Containing Algae Biomass as Potential Degradation Accelerator. Environ. Chall. 2021, 3, 100067. [Google Scholar] [CrossRef]
  152. Verdi, A.G.; de Souza, A.G.; Rocha, D.B.; de Oliveira, S.A.; Alves, R.M.V.; dos Santos Rosa, D. Biodegradable Films Functionalized with Moringa Oleifera Applied in Food Packaging. Iran. Polym. J. 2021, 30, 235–246. [Google Scholar] [CrossRef]
  153. Hoffmann, R.; Morais, D.D.S.; Braz, C.J.F.; Haag, K.; Wellen, R.M.R.; Canedo, E.L.; de Carvalho, L.H.; Koschek, K. Impact of the Natural Filler Babassu on the Processing and Properties of PBAT/PHB Films. Compos. Part Appl. Sci. Manuf. 2019, 124, 105472. [Google Scholar] [CrossRef]
  154. Cree, D.; Soleimani, M. Bio-Based White Eggshell as a Value-Added Filler in Poly(Lactic Acid) Composites. J. Compos. Sci. 2023, 7, 278. [Google Scholar] [CrossRef]
  155. Ashok, B.; Naresh, S.; Reddy, K.O.; Madhukar, K.; Cai, J.; Zhang, L.; Rajulu, A.V. Tensile and Thermal Properties of Poly(Lactic Acid)/Eggshell Powder Composite Films. Int. J. Polym. Anal. Charact. 2014, 19, 245–255. [Google Scholar] [CrossRef]
  156. Betancourt, N.G.; Cree, D.E. Mechanical Properties of Poly (Lactic Acid) Composites Reinforced with CaCO3 Eggshell Based Fillers. MRS Adv. 2017, 2, 2545–2550. [Google Scholar] [CrossRef]
  157. Rodrigues, P.V.; Cunha, A.B.; Andrade, M.A.; Vilarinho, F.; Machado, A.V.; Castro, M.C.R. Blown Film of PLA for Packaging with Green Tea and Fish Industrial Residues: An Insight on Their Properties. Food Packag. Shelf Life 2024, 43, 101283. [Google Scholar] [CrossRef]
  158. Wu, C.-S.; Wu, D.-Y.; Wang, S.-S. Preparation, Characterization, and Performance of Bio-Based Polyester Composites Derived from Renewable Distillers Grains and Shellfish. J. Polym. Res. 2021, 28, 114. [Google Scholar] [CrossRef]
  159. Yang, F.; Ye, X.; Zhong, J.; Lin, Z.; Wu, S.; Hu, Y.; Zheng, W.; Zhou, W.; Wei, Y.; Dong, X. Recycling of Waste Crab Shells into Reinforced Poly (Lactic Acid) Biocomposites for 3D Printing. Int. J. Biol. Macromol. 2023, 234, 122974. [Google Scholar] [CrossRef] [PubMed]
  160. Scaffaro, R.; Citarrella, M.C.; Catania, A.; Settanni, L. Green Composites Based on Biodegradable Polymers and Anchovy (Engraulis Encrasicolus) Waste Suitable for 3D Printing Applications. Compos. Sci. Technol. 2022, 230, 109768. [Google Scholar] [CrossRef]
  161. Scaffaro, R.; Gulino, E.F.; Citarrella, M.C. Sandwich-Structured Bimodal Polymeric Fiber/Waste Wool Fiber Bio-Composite Membrane for High-Performance and Eco-Friendly Air Filtration. Sep. Purif. Technol. 2026, 380, 135543. [Google Scholar] [CrossRef]
Preprints 187577 g001
Figure 1. European plastic production in 2022 and its conversion into plastic products by applications. Data from 2022 Plastics Europe estimations – Eurostat [4].
Figure 1. European plastic production in 2022 and its conversion into plastic products by applications. Data from 2022 Plastics Europe estimations – Eurostat [4].
Preprints 187577 g001
Preprints 187577 g002
Figure 2. Overview of the classification of polymeric materials according to their origin (bio-based vs. fossil-based) and end-of-life behavior (biodegradable vs. non-biodegradable).
Figure 2. Overview of the classification of polymeric materials according to their origin (bio-based vs. fossil-based) and end-of-life behavior (biodegradable vs. non-biodegradable).
Preprints 187577 g002
Preprints 187577 g003
Figure 3. Classification of natural waste fillers used in biocomposites, grouped into plant-based and animal-based categories.
Figure 3. Classification of natural waste fillers used in biocomposites, grouped into plant-based and animal-based categories.
Preprints 187577 g003
Preprints 187577 g004
Figure 4. Ground rice husks (a) and hazelnut shells powder (b). Reprinted (adapted) with permission from [65,91].
Figure 4. Ground rice husks (a) and hazelnut shells powder (b). Reprinted (adapted) with permission from [65,91].
Preprints 187577 g004
Preprints 187577 g006
Figure 6. Cellulose extraction from Eucomis autumnalis leaves (a,b) and from wastepaper residues (c,d). Reprinted (adapted) with permission from [134,138].
Figure 6. Cellulose extraction from Eucomis autumnalis leaves (a,b) and from wastepaper residues (c,d). Reprinted (adapted) with permission from [134,138].
Preprints 187577 g006
Preprints 187577 g007
Figure 7. Images of as-received fibrous ball of Posidonia oceanica (Egagropili) (a) and Posidonia oceanica fibers after the cleaning process (b). Reprinted (adapted) with permission from [147].
Figure 7. Images of as-received fibrous ball of Posidonia oceanica (Egagropili) (a) and Posidonia oceanica fibers after the cleaning process (b). Reprinted (adapted) with permission from [147].
Preprints 187577 g007
Preprints 187577 g008
Figure 8. semi-crushed eggshells (a), washing/rinsing step (b), and finely ground eggshell powder (c). Reprinted (adapted) with permission from [154].
Figure 8. semi-crushed eggshells (a), washing/rinsing step (b), and finely ground eggshell powder (c). Reprinted (adapted) with permission from [154].
Preprints 187577 g008
Preprints 187577 g009
Figure 9. Biodegradability tests of biocomposite film in soil (a) and injected ones in composting conditions. Reprinted (adapted) with permission from [87,95].
Figure 9. Biodegradability tests of biocomposite film in soil (a) and injected ones in composting conditions. Reprinted (adapted) with permission from [87,95].
Preprints 187577 g009
Preprints 187577 g010
Figure 10. Fertilizer release as function of time for free NPK and 3D-printed devices (a, b); pictorial description of NPK release mechanism (c). Reprinted (adapted) with permission from [94].
Figure 10. Fertilizer release as function of time for free NPK and 3D-printed devices (a, b); pictorial description of NPK release mechanism (c). Reprinted (adapted) with permission from [94].
Preprints 187577 g010
Preprints 187577 g011
Figure 11. Prototype of biodegradable food containers (a) and biocomposites samples (b) obtained for injection molding; biocomposite filament for 3D printing applications (c); biocomposite film for food packaging applications (d). Reprinted (adapted) with permission from [67,77,87,91].
Figure 11. Prototype of biodegradable food containers (a) and biocomposites samples (b) obtained for injection molding; biocomposite filament for 3D printing applications (c); biocomposite film for food packaging applications (d). Reprinted (adapted) with permission from [67,77,87,91].
Preprints 187577 g011
Preprints 187577 g012
Figure 12. Biocomposites samples (MBF) and their disintegration rate at different reprocessing cycles. Reprinted (adapted) with permission from [130].
Figure 12. Biocomposites samples (MBF) and their disintegration rate at different reprocessing cycles. Reprinted (adapted) with permission from [130].
Preprints 187577 g012
Preprints 187577 g013
Figure 13. PLA/CNC bionanocomposite prototypes showing the material behaviour before, during, and after heat-activated shape memory response: (a–c) cross-patterned prototype; (d–f) grid-patterned prototype. Reprinted (adapted) with permission from [133].
Figure 13. PLA/CNC bionanocomposite prototypes showing the material behaviour before, during, and after heat-activated shape memory response: (a–c) cross-patterned prototype; (d–f) grid-patterned prototype. Reprinted (adapted) with permission from [133].
Preprints 187577 g013
Preprints 187577 g014
Figure 14. Carbon powder adsorbed on PLA, PLA/OFI, PLA/POL by electrostatic interactions (a); air filtration mechanism of PLA/POL membranes (b). Reprinted (adapted) with permission from [148].
Figure 14. Carbon powder adsorbed on PLA, PLA/OFI, PLA/POL by electrostatic interactions (a); air filtration mechanism of PLA/POL membranes (b). Reprinted (adapted) with permission from [148].
Preprints 187577 g014
Preprints 187577 g015
Figure 15. Injection molded specimens of PLA and eggshells biocomposites (a); sandwich-structured membranes based on waste wool fibers (WWF) produced by combining a central layer of hot-pressed wool fibers with two layers of fibrous membrane based on PLA and waste wool powder (WWP) obtained by solution blow spinning technique and tested for air filtration application (b). Reprinted (adapted) with permission from [154,161].
Figure 15. Injection molded specimens of PLA and eggshells biocomposites (a); sandwich-structured membranes based on waste wool fibers (WWF) produced by combining a central layer of hot-pressed wool fibers with two layers of fibrous membrane based on PLA and waste wool powder (WWP) obtained by solution blow spinning technique and tested for air filtration application (b). Reprinted (adapted) with permission from [154,161].
Preprints 187577 g015
Table 1. Matrices, fillers, and treatments of biocomposites based on agricultural and agro-industrial waste.
Table 1. Matrices, fillers, and treatments of biocomposites based on agricultural and agro-industrial waste.
Matrix Filler Sample Code Area Mechanical Treatment Drying Temp. [°C] Drying Time [h] Other
Treatments 		Coupling Agent Ref.
PLA Artichoke plants PLA/AP Europe Ground and sieved 60 12 - - [51]
PLA Banana PLA/BF Asia - 90 6 - - [52]
PLA Cocoa Bean Shell PLA/CBSW Europe Milled and sieved 60 24 - - [53]
PLA Cocoa Husk PLA/CH South America Knife mill and sieved 60 12 - - [54]
PLA Grape
Pomace		 PLA/GP Europe Milled and sieved 48 72 - - [55]
PLA Hazelnut Shell PLA/HSF - UC mill and sieved 60 24 - - [56]
PLA Hazelnuts Shell PLA/HSF Europe Milled and sieved 60 16 - - [57]
PLA Hedysarum coronarium PLA/HC Europe Ground and sieved 90 ~16 on - - [58]
PLA Mango Seed PLA/MS South America Milled and sieved 52 24 - - [59]
PLA Olive Wood PLA/OW Europe UC mill and sieved 60 - - - [60]
PLA Opuntia
Ficus Indica		 PLA/OFI Europe Ground and sieved 90 ~16 on - - [61]
PLA Opuntia
Ficus-Indica		 PLA/OFI Europe HS mill and sieved 70 ~16 on - - [62]
PLA Orange Peel PLA/OPP Europe Ground and sieved 60 18 - - [63]
PLA Rice husk PLA/RH Asia Ground and sieved 90 12 - yes [64]
PLA Rice husk PLA/MNRH Asia - - - Alkaline
treatment 		- [65]
PLA Rice Straw PLA/RS Asia Milled and sieved 105 12 - yes [66]
PLA Rice Straw PLA/RS Asia Knife mill and sieved 80 6 - yes [67]
PLA Rice straw PLA/RSP Asia Ground and sieved 60 12 - - [68]
PLA Sesame Husk PLA/SSHP Asia Milled and sieved 50 36 - - [69]
PLA Tangerines PLA/TPF Europe UC mill and sieved 40 48 - yes [70]
PLA Tomato Peel PLA/THP Europe Milled and sieved 60 8 Alkaline
extraction		 - [71]
PLA Wheat
Middling		 PLA/WM Europe Milled and sieved 75 1 - - [72]
PLA Wheat Wastes PLA/WW Europe - - - - - [73]
PCL Date Seed PCL/DS Europe Ground and sieved - - - - [74]
PCL Olive Stones PCL/OS Europe Ground and sieved - - - [74]
PCL Waste Bean PCL/WaB Europe - 50 ~16 on - - [75]
PCL Wheat Bran PCL/WhB Europe Ground and sieved - - - - [74]
PBS Apple
Pomace		 PBS/AP Asia Milled and sieved 80 12 - yes [76]
PBS Cocoa bean shells PBS/CBS South America Ground and sieved 80 16 - -- [77]
PBS Almond Shell Flour PBS/ESF Europe Milled and sieved 50 24 - yes [78]
PBS Onion Peels PBS/OP Europe Knife mill and sieved 60 24 - - [79]
PBSA Almond Shell PBSA/AS North America Ground and sieved 68 48 - yes [80]
PHA Pineapple leaf PHA/PL Asia Ground and sieved - - Alkaline
treatment		 - [81]
PHA Rice Husk PHA/RH Asia Ground and sieved 105 24 - - [82]
PHB Almond shell PHB/AS Europe Ground and sieved 60 24 - - [83]
PHB Rice Husk PHB/RH Europe UC mill 60 24 - - [83]
PHB Seagrass PHB/SG Europe UC mill 60 24 - - [83]
PHBV Peach Palm PHBV/PP South America Ground and sieved 60 48 - - [84]
PBAT Corn stover PBAT/CS Asia Ground and sieved 80 12 - - [85]
PBAT Mangosteen PBAT/M Asia Ground and sieved 80 2 - - [86]
PLA/PBAT Corn Stover PLA/PBAT/CS Asia - 50 - - [87]
Mater-Bi® Almond Shell MB/AS Europe Milled and sieved 105 24 - - [88]
Mater-Bi® Almond Shell MB/AS Europe Milled and sieved 102 24 - - [89]
Mater-Bi® Grape
Pomace 		MB/GP Europe Milled and sieved 80 ~16 on - - [90]
Mater-Bi® Hazelnut Shells MB/HS Europe - 60 4 - - [91]
Mater-Bi® Hedysarum coronarium MB/HC Europe Ground and sieved 60 ~16 on - - [92]
Mater-Bi® Opuntia
Ficus Indica		 MB/OFI Europe Ground and sieved 90 ~16 on - - [93]
Mater-Bi® Tomato Plant MB/TP Europe Ground and sieved 40 ~16 on - - [94]
Inzea® Almond Shell Inz/AS - HS mill and sieved - - - - [95]
UC: ultra-centrifugal; HS: high speed; on: over night.
Table 3. Matrices, fillers, and treatments of biocomposites based on cellulose and derivatives waste.
Table 3. Matrices, fillers, and treatments of biocomposites based on cellulose and derivatives waste.
Matrix Cellulose Type Sample Code Area Mechanical Treatment Drying Temp. [°C] Drying Time [h] Other
Treatments 		Additive Ref.
PLA Nanocrystal
(eucalyptus)		 PLA/CNC Africa Freeze-dried - - - - [133]
PLA Eucomis
autumnalis		 PLA/EA Africa Ground and sieved - - Sodium
chloride 		- [134]
PLA Lignin
(corn cob)		 PLA/Lignin Asia - 80 12 - Plasticizer [135]
PLA Micro-fibrillated PLA/MFC Europe - - - - - [136]
PLA Nanocellulose (agro-industrial) PLA/NCs South America - - - Bleaching - [137]
PLA Waste Paper PLA/WP Europe UC mill and sieved 60 24 Fatty acid ester - [138]
PCL Microcrystalline (durian rind) PCL/MCC Asia Ground and sieved 100 24 Alkaline and bleaching - [139]
PCL Cellulose
(agricultural)		 PCL/CNC Asia Ground and sieved - - - - [140]
PCL Nanocrystal
(luffa cylindrica)		 PCL/MLW South America - - - Acid and bleaching Compatibilizer [141]
PBAT Lignin
(black liquor)		 PBAT/lignin Europe - 80 12 - - [142]
PBAT Microcrystalline (almond shells) PBAT/as-MCC Europe Ground and sieved 80 4 - - [143]
PVA Cellulose acetate (potato peel) PVA-CA/Starch Asia Ground and sieved - - - - [144]
PVA Nanofibrils
(coconut)		 CCNF/PVA Asia - - - Alkaline and bleaching - [145]
UC: ultra-centrifugal.
Table 4. Matrices, fillers, and treatments of biocomposites based on alternative organic waste.
Table 4. Matrices, fillers, and treatments of biocomposites based on alternative organic waste.
Matrix Filler Sample Code Area Mechanical Treatment Drying Temp. [°C] Drying Time [h] Additive Ref.
PLA Posidonia
Oceanica leaves		 PLA/PO Europe Ground and sieved 80 12 - [146]
PLA Egagropili PLA/POS Europe Crushed 65 12 DCP,
Plasticizer		 [147]
PLA Posidonia
Oceanica leaves		 PLA/POL Europe Ground and sieved 60 12 - [148]
PLA Aloe Vera PLA/AV S. America - 60 16 - [149]
PLA Posidonia
Oceanica leaves		 PLA10A Europe Ground and sieved 90 12 - [150]
PLA Duneleila
Tertiolecta Algae		 PLA/AB Asia - - - - [151]
PBAT Moringa
oleifera		 PBAT/MO S. America Ground and sieved 60 24 - [152]
PBAT/PHB Babassu PBAT/PHB/BS Europe Ground and sieved 60 20 - [153]
DCP: Dicumyl peroxide.
Table 6. Processing, properties application and end of life of biocomposites based on agricultural and agro-industrial waste.
Table 6. Processing, properties application and end of life of biocomposites based on agricultural and agro-industrial waste.
Sample Code Processing Key Results Application End of Life Ref.
PLA/AP MC + Hot process ↑ Elastic modulus Variety of Fields - [51]
PLA/BF MC + Inject. mould. ↑ Flexure and
tensile strength		 - - [52]
PLA/CBSW MC + 3D printing ↑ Rigidity and load
resistance		 3D printing filament - [53]
PLA/CH MC+ 3D printing ↑ Tensile strength 3D printing filament - [54]
PLA/GP MC + Film blowing ↑ Antioxidant and
antimicrobial activity		 Packaging - [55]
PLA/HSF MC + Inject. mould. ↑Flexural modulus and sustainability Building industry - [56]
PLA/HSF MC + Inject. mould. Easily scalable - - [57]
PLA/HC MC + Compress. mould.
MC + 3D printing		 ↑ Elastic modulus
Excellent printability		 -
Automotive 		-
-		 [58]
PLA/MS MC + Inject. mould. ↑ Barrier properties Packaging - [59]
PLA/OW MC + 3D printing ↑ Porosity Non-structural - [60]
PLA/OFI MC + 3D printing Good processability 3D printing filament - [61]
PLA/OFI MC + Compress. mould. ↑ Stiffness Packaging [62]
PLA/OPP Solvent casting ↑ Biodegradation - Soil burial [63]
PLA/RH MC + 3D printing ↑ Tensile strength and
improved adhesion		 3D printing filament - [64]
PLA/MNRH MC + 3D printing ↑ Mechanical and thermal properties Automotive - [65]
PLA/RS MC + Compress. mould. Improve interfacial
Adhesion		 - - [66]
PLA/RS MC + Inject. mould. - - [67]
PLA/RSP MC + 3D printing ↑ Flexure and tensile strength 3D printing filament Soil burial [68]
PLA/SSHP Solvent casting ↑ Tensile and thermal properties Packaging Soil degradation [69]
PLA/TPF MC + Inject. mould. ↑ Biodegradation - Compost soil [70]
PLA/THP Solvent casting +
compress. mould.		 ↑ Tensile strength Packaging - [71]
PLA/WM MC + 3D printing Good filler dispersion 3D printing filament - [72]
PLA/WW MC + 3D printing ↑ Sustainability 3D printing filament - [73]
PCL/DS MC + Hot process ↑Modulus and
thermal stability		 Packaging - [74]
PCL/OS MC+ Hot process ↑Modulus and
thermal stability		 - - [74]
PCL/WaB MC + Compress. mould. ↑Modulus and
thermal stability		 Industrial - [75]
PCL/WhB MC + Hot process Plasticization effect Industrial - [74]
PBS/AP MC + Inject. mould. ↑ Impact and tensile strength - - [76]
PBS/CBS MC + 3D printing ↑ Modulus Packaging - [77]
PBS/ESF MC + Inject. mould. ↑ Disintegration rate 3D printing filament Disintegration
in soil		 [78]
PBS/OP MC + Inject. mould. ↑ Ductile properties
(with compatibilizers)		 Automotive - [79]
PBSA/AS MC + Inject. mould ↑Mechanical properties (with compatibilizers) Packaging - [80]
PHA/PL MC + Hot process ↑Biodegradation Packaging - [81]
PHA/RH MC + Hot process ↑Biodegradation - - [82]
PHB/AS MC + Hot process ↑Permeability Packaging Disintegration [83]
PHB/RH MC + Hot process ↑Mechanical properties Packaging Disintegration [83]
PHB/SG MC + Hot process ↑Mechanical properties Packaging Disintegration [83]
PHBV/PP MC + Inject. mould. ↑Biodegradation Packaging Soil burial [84]
PBAT/CS MC + Compress. mould. ↑ Stiffness Packaging - [85]
PBAT/M MC + Compress. mould. ↑ Thermal stability Packaging - [86]
PLA/PBAT/CS MC + Inject. mould. ↑Mechanical properties Packaging Soil burial [87]
MB/AS MC + Inject. mould. ↑Biodegradation Packaging Soil burial [88]
MB/AS MC + Inject. mould. ↑Mechanical properties Packaging - [89]
MB/GP MC + Compress. mould. Good fertilizer release 3D printing filament - [90]
MB/HS MC + Inject. mould. ↑ Ductility - - [91]
MB/HC MC + 3D printing ↑ Rigidity - - [92]
MB/OFI MC + 3D printing ↑ Fertilizer release - - [93]
MB/TP MC + 3D printing ↑Mechanical properties 3D printing filament - [94]
Inz/AS MC + Inject. mould. ↑Mechanical properties - Compost soil [95]
MC: melt compounding.
Table 7. Processing, properties application and end of life of biocomposites based on natural fibers waste.
Table 7. Processing, properties application and end of life of biocomposites based on natural fibers waste.
Sample Code Processing Key Results Application End of Life Ref.
PLA/AI MC + Inject. mould. ↑Mechanical Properties Industrial - [96]
PLA/AF MC + 3D printing ↑Impact tensile 3D printing filament Compost in soil [97]
PLA/BF MC+ Inject. mould. ↑Mechanical and Thermal Properties Variety of fields - [98]
PLA/BF MC+ Inject. mould. ↑Recycling Variety of fields - [99]
PLA/CS MC+ Inject. mould. Low interfacial adhesion - - [100]
PLA/EG MC+ Inject. mould. ↑Mechanical Properties and Bio - Soil degradation [101]
PLA/CFY Extr. coating + 3D printing ↑Mechanical Properties 3D printing filament - [102]
PLA/Flax MC+ Compress. mould. ↑Tensile strength - - [103]
PLA/FS Direct Extr. process ↑Impact and tensile modulus Automotive - [104]
PLA/FS Direct Extr. process ↑ l/d ratio at low rotational speed 3D printing filament - [105]
PLA/HS MC+ Compress. mould. ↑Biodegradation - Soil degradation [106]
PLA/THF Direct Inject. mould. ↑Mechanical and Thermal Properties Non-structural - [107]
PLA/Jute MC+ Compress. mould. ↑Resistence creep - - [103]
PLA/KF MC + 3D printing ↑Toughness 3D printing filament - [108]
PLA/KF MC+ Compress. mould. ↑Mechanical Properties - Soil burial [109]
PLA/KFA MC+ Inject. mould. ↑Mechanical and water resistance - - [110]
PLA/LK MC + Hot process ↑Mechanical Properties - - [111]
PLA/WK MC+ Hot process ↑Mechanical Properties Automotive - [112]
PLA/PS MC+ Inject. mould. ↑Biodegradation - Compost in soil [113]
PLA/SF MC+ Inject. mould. ↑Mechanical and Thermal Properties Non-structural - [114]
PLA/SF MC+ Inject. mould. ↑Impact and tensile modulus - - [115]
PLA/SF MC+ Inject. mould. ↑Mechanical Properties - - [116]
PLA/MS MC+ Inject. mould. ↑Mechanical Properties - - [117]
PCL/DP MC+ Compress. mould. ↑Mechanical Properties - - [118]
PCL/HF MC+ Compress. mould. ↑Mechanical Properties Packaging - [119]
PCL/DP MC+ Compress. mould. ↑ Flexure and tensile strength - - [120]
PBS/C MC+ Compress. mould. ↑Mechanical Properties Packaging - [121]
PBS/HF MC+ Compress. mould. ↑Sustainability - Enzymatic hydrolysis and soil burial [122]
PHA/PLF MC+ Hot pression ↑Biodegradation 3D printing filament Soil burial [81]
PHB/SF MC+ Compress. mould. ↑Recycling - - [123]
PHBV/AF MC+ Inject. mould. ↑Mechanical properties (with Alkali treatment) - Aqueous
environment		 [124]
PBAT/CF MC+ Compress. mould. ↑Mechanical Properties - - [125]
PBAT/MF MC+ Compress. mould. ↑Mechanical Properties - - [125]
PBAT/TF MC+ Compress. mould. ↑Mechanical Properties - - [125]
PBAT/CS Solvent casting ↑ Antioxidant and antimicrobial activity Packaging - [126]
PBAT/HF Open blending + Hot press ↑Biodegradation - Soil burial [127]
PBAT/KF MC+ Hot process ↑Mechanical properties (with compatibilizers) - - [128]
PBAT/F MC + 3D printing ↑Stiffness and strength 3D printing filament - [129]
MB/AF MC+ Compress. mould. ↑Recycling - Compost in soil [130]
MC: melt compounding.
Table 8. Processing, properties application and end of life of biocomposites based on cellulose and derivatives waste.
Table 8. Processing, properties application and end of life of biocomposites based on cellulose and derivatives waste.
Sample Code Processing Key Results Application End of Life Ref.
PLA/CNC MC+ 3D printing ↑ Mechanical,
shape memory		 4D applications - [133]
PLA/EA MC + Compress Mould. No significant changes 3D printing filament - [134]
PLA/Lignin MC + 3D printing ↑ Elongation and
toughness		 Biomedical - [135]
PLA/MFC MC + Film Blowing ↑ Mechanical Packaging - [136]
PLA/NCs MC + Compress Mould. ↑ Mechanical Packaging - [137]
PLA/WP Melt compounding ↑ Mechanical,
sustainability		 Packaging - [138]
PCL/MCC Melt compounding ↑ Mechanical,
biodegradability		 - Soil degradation [139]
PCL/CNC Solution casting ↑ Tensile Strength - - [140]
PCL/MLW Solution casting ↑ Modulus - - [141]
PBAT/lignin MC + Film Blowing ↑ Modulus,
photo degradation		 Packaging - [142]
PBAT/as-MCC MC + Compress Mould ↑ Modulus - - [143]
PVA-CA/Starch Solution casting ↑ Mechanical,
biodegradability		 - Enzymatic degradation [144]
CCNF/PVA Solution casting ↑ Mechanical Packaging - [145]
MC: melt compounding.
Table 9. Processing, properties application and end of life of biocomposites based on alternative organic waste.
Table 9. Processing, properties application and end of life of biocomposites based on alternative organic waste.
Sample Code Processing Key Results Application End of Life Ref.
PLA/PO Compression molding ↑ Sustainability - - [146]
PLA/POS Injection molding ↑ Ductility, Sustainability - - [147]
PLA/POL Electrospinning ↑ Mechanical, Sustainability Air filtration - [148]
PLA/AV Injection molding ↑ UV resistance - - [149]
PLA10A Compression molding ↑ Sustainability - - [150]
PLA/AB Extrusion ↑ Degradation, Sustainability - Compostability, soil degradation [151]
PBAT/MO Wire Extension (film) ↑ Fruit shelf life Packaging - [152]
PBAT/PHB/BS Wire Extension (film) ↑ Mechanical, Sustainability Packaging and
mulch films		 - [153]
Table 10. Processing, properties application and end of life of biocomposites based on animal waste.
Table 10. Processing, properties application and end of life of biocomposites based on animal waste.
Sample Code Processing Key Results Application End of Life Ref.
PLA/WE Injection molding ↑ Tensile modulus - - [154]
PLA/ESP Film Casting ↑ Mechanical, sustainability Packaging - [155]
PLA/WES Injection molding No significant changes - - [156]
PLA/FG Film Blowing ↑ Oxy barrier, antioxidant Packaging Compostability [157]
PLA/PUS Compression Molding ↑ Mechanical, sustainability Packaging, utensils Soil degradation [158]
PLA/CSP 3D Printing ↑ Mechanical Biomedical - [159]
PLA/EE 3D Printing ↑ Mechanical, ↑ processability, sustainability Packaging - [160]
PLA/WP Solution Blow Spinning ↑ Mechanical, sustainability Air filtration - [161]
PHA/OSP Compression Molding ↑ Mechanical, sustainability Packaging, utensils Soil degradation [81]
MB/EE 3D Printing ↑ Mechanical, sustainability Packaging - [160]
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.
Copyright: This open access article is published under a Creative Commons CC BY 4.0 license, which permit the free download, distribution, and reuse, provided that the author and preprint are cited in any reuse.
Prerpints.org logo

Preprints.org is a free preprint server supported by MDPI in Basel, Switzerland.

facebook logotwitter logolinkedin logo
bsky
MDPI Initiatives
Important Links
Subscribe

Disclaimer

Terms of Use

Privacy Policy

Privacy Settings

© 2026 MDPI (Basel, Switzerland) unless otherwise stated