主链含环三硅氮烷的聚硅氧烷的合成——环硅氮阴离子引发环硅氧烷开环聚合

在极性溶剂中合成了六苯基环三硅氮烷锂盐（Ｐ３ＮＬｉ） ．在促进剂的作用下，此锂盐成功地引发了环硅氧烷的开环聚合．通过对聚合物的含氮量、１Ｈ ＮＭＲ、２９Ｓｉ ＮＭＲ 谱的测试，结果证明所得到的聚合物中含有六苯基环三硅氮烷，并研究了聚合物的分子量（ＧＰＣ） 与特性粘数的关系．

SYNTHESIS OF POLYDIMETHYLSILOXANES IN THE MAIN CHAIN CONTAINING CYCLOTRISILAZANE

Although the catalytic activity of hexaphenylcyclo\|trisilazane trilithium salt is much lower than that of hexamethylcylotrisilazane trilithium salt due to the inductive and steric effect of phenyl group, the thermal and hydrolytic stability of hexaphenylcyclo\|trisilazane is much higher than that of hexamethylcyclotrisilazane. By using a polar solvent, such as 1,4\|dioxane,etc., hexaphenylcyclo\| trisilazane trilithium salt is prepared through the reaction of hexaphenylcycoltrisilazane and \%n\%\|BuLi at low temperature.Ring\|opening polymerization of cyclosiloxane using hexaphenylcyclotrisilazane trilithium salt as a catalyst and THF,Diglyme of DMSO as a promoter is carried out. The polymer is characterized by 1H\|NMR, 29 Si\|NMr,GPC limiting viscosity number measurement. Nitrogen content of the polymer is determined by means of coulometric titration. It is confirmed hat the polymer contains hexaphenylclotrisilazane. The relation between the weight\|average molecular weight and the limiting viscosity number of the polymer has been studied.