水性纳米SiO2改性环氧树脂/聚氨酯丙烯酸酯涂料的制备与热性能研究

制备了水性纳米SiO2改性环氧树脂（ER）／聚氨酯丙烯酸酯（PUA）复合涂料，用二苯基碘鎓盐为光引发剂研究了涂料的光-热混杂固化反应、动态力学和热降解过程。结果表明，涂料有良好的光固化性能，光-热混杂固化可进一步提高材料刚性；加入纳米SiO2可提高材料的Tg，硬度达到4H，但在高温下对材料有催化降解作用。用Friedman法研究了材料的热降解活化能Ea，证明当Nano-SiO2含量为4％热降解Ea为45．64kJ／mol，比光固化体系约提高13．60kJ／mol。在非等温条件下材料降解率不高于15％时Ea随α逐渐升高，之后随温度升高而降低。

Preparation and Thermal Properties of Nano- SiO2 Modified Epoxy Resin/Polyurethane Acrylate Waterborne Coatings

The UV-heat curing nano-SiO2 modified epoxy resin/polyurethane acrylate waterborne coating was prepared, and then, diphenyliodonium hexa-fluorophosphate （DPI · PF6） was used as a photoinitiator to research the UV-heat curing reaction, dynamic mcchanics and thermal degradation process of the coating. The results showed that the coating had a good UV curing property and the rigidity of materials could be further improved by UV-heat curing. The nano-SiO2 could improve Tg of the material, so that its hardness could reach 4H, but it had catalytic degradation for the material under a high temperature. Then, the degradation activation energy Ea was studied by Friedman method, which showed that, when nano-SiO2 accounted for 4% （wt）, Ea was 45.64 kJ/mol, about 13.60 k J/tool higher than the UV curing system. In addition, when the material degradation rate was below 15% in non-isothemlal conditions, Ea increased gradually with a and then decreased with temperature rise.