聚氨酯丙烯酸酯／SiO2纳米杂化涂层的制备及其性能研究

摘要

In this paper,firstly,nanosilica was prepared by sol-gel method,and the low molecular weight isocy-anate-terminated polyurethane prepolymer was synthesized by the reaction of hexamethylene diisocyanate ( HDI ) with different molecular weight polyethyleneglycol(PEG 200,400 and 600). Then,the prepolymer was grafted onto the surface of nanosilica to obtain polyurethane-modified nanosilica. Finally, the modified nanosilica was dispersed into polyurethane acrylate( PUA) , which was then cured by UV light to achieve nanohybrid coatings. The structure of modified nanosilica was characterized by FT-IR. Thermodynamic and mechanical properties of curing materials were investigated by differential scanning calorimetry ( DSC) ,pendulum damping tester and film impactor, respec-tively. The results indicated that the property of coating prepared by nanosilica was optimized by nanosilica, and the nanosilica was modified by PEG-400 and HDI possessed better property of heat resistance and impact resist-ance.%采用不同相对分子质量的聚乙二醇（ PEG-200、400、600）分别与六亚甲基二异氰酸酯（ HDI）反应合成预聚体，再以此预聚体对纳米SiO2进行表面接枝改性，制备了聚氨酯改性纳米SiO2；将改性纳米SiO2分散到聚氨酯丙烯酸酯（ PUA）中光固化制备了PUA／SiO2纳米杂化涂层。讨论了PEG相对分子质量对PUA／SiO2纳米杂化涂层的耐热性能和力学性能的影响，并以FT-IR、差示扫描量热法（ DSC）等进行表征。结果表明，改性后的纳米SiO2粒子优化了PUA树脂的性能，且以PEG-400与HDI合成的预聚体来改性纳米SiO2用于制备的PUA／SiO2纳米杂化涂层具有较好的耐热性和抗冲击性。