含氢苯基硅树脂的制备及其在涂层中的应用∗

摘要

在固体酸催化下,以苯基三乙氧基硅烷(PTES)、二甲基二乙氧基硅烷(DMES)、四甲基环四硅氧烷(D4 H )、八甲基环四硅氧烷(D4)、六甲基二硅氧烷(MM)和四甲基二硅氧烷(D2 H )为主要原料,通过水解缩聚法合成了一系列Si—H 键、D链节含量分别不同的含氢苯基硅树脂 HPSR.用傅里叶变换红外光谱(FT-IR)和核磁共振氢谱(1 H NMR)对其进行了结构表征.将所制的 HPSR与乙烯基硅橡胶VPS以n(Si—H)∶n(Vi)＝1．2∶1．3的摩尔比混合,并加入剂量的络合铂催化剂、铂抑制剂,以及占总质量10％的白炭黑和钛白粉,在160℃下固化10~15 min即制得透明的耐高温硅橡胶涂层,并对其耐热性和力学性能进行研究.结果表明,当 HPSR 分子中Si—H 键含量为5 mmol/g,MD∶MR＝10％时,对应制备的涂层耐热性、柔韧性以及力学性能最佳.%The hydrogen containing phenyl silicone resin (HPSR)was synthesized with hydrolysis-polyconden-sation method from phenyltriethoxysilane (PTES),methyltriethoxysilane (MTES),teteamethylcyclotetrasi-loxane (D4 H ),octamethylcyclotetrasioxane (D4 ),hexamethyldisiloxane (MM)and teteamethyldisiloane (D2 H ) in the presence of solid acid catalyst,which has different content of Si—H and D chain respectively.The struc-ture of the polymer was characterized through FT-IR and 1 H NMR.The HPSR and vinyl silicone rubber (VPS) was mixed with the molar ratio of n(Si—H)∶n(Vi)=1.2∶1.3,together with the dose of Pt catalyst,Pt inhib-itor,and 10% of silica and titanium dioxide,the high temperature silicone rubber coating was successively pre-pared with 160 ℃ sustained 10-15 min,and the high temperature and mechanical properties were also studied. the results showed that when content of HPSR Si—H was 5 mmol/g,MD∶MR=10%,high resistance,flexi-bility and mechanical properties of the coating were the best.