聚二甲基硅氧烷—苯基倍半硅氧烷共聚物及其弹性体

POLYDIMETHYLSILOXAE PHENYLSILSESQUIOXANE COPOLYMER AND ITS ELASTOMER

以苯基三甲氧基硅烷和羟基封端的聚二甲基硅氧烷为原料，在有机溶剂中进行碱催化水解、缩合反应．形成了聚二甲基硅氧烷－苯基倍半硅氧烷共聚物．当Ｈ２Ｏ与ＰｈＳｉ（ＯＣＨ３）３的摩尔比ＲＷ／Ｓｉ＞１．５时．形成的共聚物发生分层或交联；在０．８＜ＲＷ／Ｓｉ＜１．５的情况下，共聚物为一种白色有机硅流体。通过ＦＴＩＲ和１Ｈ—ＮＭＲ光谱研究表明，这种可流动的共聚物是由聚二甲基硅氧烷链段和具有不完整梯形结构的苯基倍半硅氧烷链组成的．它能够在室温下硫化成力学性能优异的有机硅弹性体。

The base-catalyzed hydrolysis and condensation of phenyltrimethoxysilane in the presence of Hydroxy-terminated polydimethylsiloxane in organic solvents produced a polydimethylsiloxanephenylsilsequioxane copolymer.The copolymer leads to cross-linking or phase seperation when the molar ratio of H2O to Phsi(OCH3)3 Rw/si> 1.5. In the case of 0.8< Rw/si<1.5,the copolymer is a white silicone fluide.The investigation of the copolymer structure by FTIR and 1HNMR spectroscopy showea that it is composed of polydimethylsiloxane and phenylsilsesquioxane segments with incomplete ladder structures.The copolymer can be vulcanized to a silicone elastomer with good mechan,caf properties at room temperature.