巯基/烯丙基/环氧水性杂化涂料的制备与性能

Preparation and Properties of Hybrids Waterborne Coating Containing Thiol/Allyl/Epoxy Groups

采用可逆加成-断裂链转移自由基(RAFT)乳液聚合方法,制得聚甲基丙烯酸烯丙酯(P-AMA)和聚甲基丙烯酸缩水甘油酯(P-GMA)RAFT乳液,并将2种乳液按比例与巯基封端的聚氨酯水分散体(PU-SH)混合成膜,得到具有最佳涂膜性能的杂化涂料配方。采用傅里叶变换红外光谱仪(FT-IR)对乳液及涂膜的结构进行表征,用差示扫描量热仪(DSC)等仪器对涂膜的性能进行研究,结果表明:水性杂化体系中的巯基与烯丙基在紫外光照的条件下发生巯基-烯丙基点击反应,与环氧基在受热的条件下发生了环氧开环反应。杂化涂料在经光/热双重固化后涂膜的吸水率为30%、凝胶量为99%、耐溶剂(丁酮)擦试为330次、铅笔硬度为5H、耐冲击性为50 cm。

Polyallylmethacrylate emulsion （ P - AMA） and polyglycidylmethacrylate emulsion （ P - GMA ） were prepared by reversible addition - fragmentation chain transfer radical（RAFT） emulsion polymerization. A waterborne hybrid coating formula was obtained by blend of P - AMA and P - GMA at an optimized ratio and thiol - terminated polyurethane water dispersion （ PU - SH）. The structures of emulsion and films were charactered by FT- IR. The properties of the films were tested by differential scanning calorimeter（DSC） and other instruments. It was indicated that thiol - allyl click reaction and epoxy ring opening reaction were performed in the presence of UV or heat under UV/hot dual curing conditions. The cured hybrids films showed good properties, gel content 99% , solvent -resistance（ MEK rub） 330 times, pencil hardness 5H, and impact strength 50 cm, respectively.