三元巯基／乙烯基硅氮烷UV固化制备聚合物陶瓷前驱体

采用差光量热扫描研究了三元巯基化合物与乙烯基硅氮烷紫外光固化特性,结果表明,随着光引发剂浓度和辐照强度的增加,体系聚合速率增大,体系终止方式以自由基双基偶合终止为主。聚合反应为一级,且聚合速率与乙烯基浓度有关,而与巯基浓度无关。对制备的聚合物陶瓷前驱体的基本性能进行了分析,结果表明,玻璃化转变温度随巯基化合物用量的减少而降低,在巯基-乙烯基硅氮烷等摩尔比时,体系的固化度最大。

Preparation of Polymer Derived Ceramic Precursor of Thiol-Vinyl Silazane Cured by UV

The UV curing characteristics of three functional thiol compound-vinyl silazane were investigated by differential photo-scanning calorimetry.The polymerization rate of this system increases with increasing of the concentration of photoinitiator or enhancing UV intensity,and this curing system is dominated by bimolecular radical termination.The polymerization rate is first-order overall with first-order dependence on vinyl functional group concentration and independent of thiol functional group concentration.DMA results show that the Tg of the copolymer cured by UV falls down with decreasing of the amount of thiol compound.The peak value of the curing degree of the copolymer appears at the stoichiometric ratio of thiol to vinyl silazane.