The increasing pursuit of biocontained elastic materials led the investigation of the potential use of the monoterpene limonene in film synthesis via thiol–ene reaction. Poly[(mercaptopropyl)methylsiloxane] (PMMS) is first synthesized. By controlling the molar ratio of PMMS and functional monomers, such as polyethylene glycol allyl methyl ether or rhodamine-B, PMMS is partially functionalized while leaving spare mercapto groups that could be further used as cross-linking sites. On the basis of the functionalized PMMS, novel transparent silicone luminescent films with hydrophilic tunable properties are prepared by natural-sunlight-triggered thiol–ene “click” chemistry by using d -limonene as a cross-linker. Their structures and properties are thoroughly characterized. Transparent luminescent films are coated on commercially available UV-light emitting diode (LED) cell from solution medium followed by an in situ cross-linking step; a colorful LED cell is obtained through this facile and efficient method. The UV-LED coated by films show very intense photoluminescence under normal visible light or the light is on, and has very high coloric purity.
In order to control d-limonene permeability, cellulose nanocrystals (CNC) were used to regulate starch-based film multiscale structures. The effect of sphere-like cellulose nanocrystal (CS) and rod-like cellulose nanocrystal (CR) on starch molecular interaction, short-range molecular conformation, crystalline structure, and micro-ordered aggregated region structure were systematically discussed. CNC aspect ratio and content were proved to be independent variables to control d-limonene permeability via film-structure regulation. New hydrogen bonding formation and increased hydroxypropyl starch (HPS) relative crystallinity could be the reason for the lower d-limonene permeability compared with tortuous path model approximation. More hydrogen bonding formation, higher HPS relative crystallinity and larger size of micro-ordered aggregated region in CS0.5 and CR2 could explain the lower d-limonene permeability than CS2 and CR0.5, respectively. This study provided new insight for the control of the flavor release from starch-based films, which favored its application in biodegradable food packaging and flavor encapsulation.
危险品化学品经营许可证（带存储）