无溶剂双组分BN/环氧/VMQ杂化聚硅氧烷涂料的研制

Development of Solventless Two-Component BN/Epoxy/VMQ Hybrid Polysiloxane Coatings

采用物理方法将烯丙基缩水甘油醚、纳米乙烯基甲基MQ硅树脂(VMQ)、硅烷偶联剂KH560和改性微米级导热氮化硼(BN)填料混杂分散在低黏度端乙烯基甲基硅油中,通过交联剂含氢甲基硅油、抑制剂乙炔基环己醇及Karstedt催化剂,制成室温流动性好、操作时间长的无溶剂型双组分BN/环氧/VMQ杂化聚硅氧烷涂料,并探讨了涂料的交联固化成膜机理。试验结果表明:通过VMQ改性的聚硅氧烷涂膜,拉伸强度和粘接强度显著提高,再经环氧改性后的粘接强度可进一步提高到1.2 MPa;随着BN掺量的增加,涂膜的导热率大幅提升。当乙烯基硅油质量为100份、VMQ为90份、烯丙基缩水甘油醚为2份和BN为60份时,热固化形成的杂化聚硅氧烷涂膜导热率可达到1.6 W/(m·K),失重10%时的温度可达631 K。

A novel solventless two component hybrid polysiloxane coatings with good fluidity and long operation time at room temperature was prepared by physically mixing low initial viscosity terminated-vinyl methyl silicone oil with allyl glycidyl ether,nano-scale vinyl methyl MQ silicone resin（VMQ）,KH560 silane coupling agent and modified micro-scale thermal-conductivity BN filler,then reaction with crossing-linking agent hydrogen containing methyl silicone oil,inhibitor ethynylcyclohexanol and catalyst Karstedt. The crosslinking curing mechanism of coatings was investigated. The tensile and adhesion strength of polysiloxane film modified by VMQ were improved,and the adhesion strength distinctively reached 1.2 MPa with the modification of epoxy. With increasing of addition of BN,thermal conductivity of the film would be greatly promoted. The heat curing film had the coefficient of heat conductivity 1.6 W/（m·K）and the decomposition temperature of 10% mass loss 631 K when the composition of vinyl methyl silicone oil 100,VMQ 90,allyl glycidyl ether 2 and BN 60.