聚硅烷的合成、表征及光敏性研究

研究了不同添加量的二甘醇二甲醚和15－冠醚－5两种助溶剂对聚（甲基乙基硅烷）简记为PM－PES）合成反应的影响，结果表明，反应体系中添加10％二甘醇（二甘醇二甲醚，甲苯的体积比），PMPES的产率明显提高，分子量趋于单分散分布，并向聚（甲基环乙基硅烷）（简主为PMCS）和甲基环乙基硅烷－甲基苯乙基硅烷共聚物（甲基环乙基二氯硅烷：甲基苯乙基二氯硅烷的单体摩尔比为2．0，1．0和0．5时，相应的共聚物分别简记为Copolymer1,Copolymer2和Copolymer3)的合成反应中添加10％二甘醇二甲醚助溶,春产率分别高达47％和52％以上，MW均达10^5 ,并且^1H-NMR,IR说烽UV吸收光谱对所合成的聚硅烷进行了表征，研究了PMCS膜在空气中经紫外光辐射前后的IR谱和高效凝胶渗透透色谱（GPC），表明，PMCS经紫外光辐照发生光降解的同时，还伴随着光氧化。

STUDIES ON SYNTHESES AND CHARACTERIZATIONS OF POLYSILANES

The effects of adding cosolvents of diglym e and 15-crown-5 to the reaction mixture of Wurtz-type coupling of dichlorosi lanes upon the yield and molecular weight dispersity of poly(methylphenethylsila ne)(PMPES) were discussed. The results show that addition of 10%(diglyme∶toluen e by volume) diglyme as a cosolvent to the reaction mixture leads to the yield i ncrease of PMPES with a monomodal distribution of molecular weight. Adding 10% ( diglyme∶toluene by volume) diglyme to the reaction mixtures, the yields of poly (methylcyclohexylsilane)(PMCS) and copolymers-poly(methylcyclohexylsilane-co- methylphenethylsilane) (the molar ratios to methylcyclohexyldichlorosilane／meth ylphenethyldichlorosilane are 2.0,1.0 and 0.5, the copolymers are ab breviated by Copolymers 1, 2 and 3, respectively) are 47% and more than 52%, respectively; their molecular weight (w) almost reach 05 . These polysilanes were characterized by 1H-NMR , IR and UV absorpton s pectrum. The photolysis of PMCS film, Which was exposed on broad-band UV light in air for different exposure time, was also investigated by GPC and IR spectrum , the results indicate that the molecular weights to PMCS are decreased and silo xane structure in silicon-silicon main chain is formed with the processes of photodegradation and photo-oxidation.