Mechanical and Durability Performance of Recycled Tetra Pak PolyAl–Rice Husk Wood-Like Boards for Urban Furniture

Global outdoor furniture consumes large amounts of virgin wood and polyolefins, while multilayer beverage cartons and rice husks are usually landfilled or burnt despite their polymer and lignocellulosic value. However, no study has yet provided experimentally validated formulations that convert both waste streams into extruded wood-like boards for low-load urban elements. This work therefore characterised hybrid composites containing 50–80 wt.% recycled Tetra Pak PolyAl and 20–50 wt.% ground rice husk, produced at pilot scale by single-screw extrusion plus compression moulding. Boards were tested for density, tensile and flexural properties, Shore D hardness, water absorption (ISO 62-inspired) and 254 nm UV ageing. Increasing rice-husk content from 20 to 50 wt.% raised Shore D hardness from 54 to 63 but almost doubled water uptake (≈45 vs 25 g m⁻² at 7 d), while UV exposure increased surface hardness by 3–5 points without visible cracking. The 70 Tetra Pak/30 rice-husk formulation gave the best balance, with a flexural modulus of 2.1 GPa and MOR of 18 MPa, exceeding the ASTM D7032 requirement for outdoor decking (MOR ≥ 11 MPa). By valorising two locally available wastes into a market-ready material, the proposed symbiosis supports circular-economy strategies for urban furniture.