Song, Y.K.; Lee, T.H.; Kim, J.C.; Lee, K.C.; Lee, S.-H.; Noh, S.M.; Park, Y.I. Dual Monitoring of Cracking and Healing in Self-healing Coatings Using Microcapsules Loaded with Two Fluorescent Dyes. Molecules2019, 24, 1679.
Song, Y.K.; Lee, T.H.; Kim, J.C.; Lee, K.C.; Lee, S.-H.; Noh, S.M.; Park, Y.I. Dual Monitoring of Cracking and Healing in Self-healing Coatings Using Microcapsules Loaded with Two Fluorescent Dyes. Molecules 2019, 24, 1679.
Song, Y.K.; Lee, T.H.; Kim, J.C.; Lee, K.C.; Lee, S.-H.; Noh, S.M.; Park, Y.I. Dual Monitoring of Cracking and Healing in Self-healing Coatings Using Microcapsules Loaded with Two Fluorescent Dyes. Molecules2019, 24, 1679.
Song, Y.K.; Lee, T.H.; Kim, J.C.; Lee, K.C.; Lee, S.-H.; Noh, S.M.; Park, Y.I. Dual Monitoring of Cracking and Healing in Self-healing Coatings Using Microcapsules Loaded with Two Fluorescent Dyes. Molecules 2019, 24, 1679.
Abstract
We report the development of an extrinsic self-healing coating system that shows no fluorescence from the intact coating, yellowish fluorescence in cracked regions, and greenish fluorescence in healed regions, thus allowing the separate monitoring of cracking and healing of coatings. This fluorescence monitoring self-healing system consisted of a top coating, an epoxy matrix resin containing mixed dye-loaded in single microcapsule. The dye-loaded microcapsules consisted of a poly(urea-formaldehyde) shell encapsulating a healing agent containing MAT-PDMS and styrene, a photo-initiator and a mixture of two dyes, one that fluoresces only in the solid state (DCM) and a second that fluoresces dramatically increased in the solid than solution state (4-TPAE). A mixture of the healing agent, photo-initiator and the two dyes was yellow due to fluorescence from DCM. On UV curing of this mixture, however, the color changed from yellow to green and the fluorescence intensity increased due to fluorescence from 4-TPAE in the solid state. When a self-healing coating embedded with microcapsules containing the DCM/4-TPAE dye mixture was scratched, the damaged region exhibited a yellowish color that changed to green after healing. Thus, the self-healing system reported here allows the separate monitoring of cracking and healing based on changes in fluorescence color.
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Young Kyu Song
, 
,