高熔点聚碳硅烷的合成及其裂解机理的研究

Study of a High Melting point Polycarbosilane Prepartion and Its Pyrolysis Mechanism

对高熔点聚碳硅烷的合成反应条件进行了较为详细的研究，并通过改变化学反应的温度、压力和反应时间制备出了熔点高达３８０ ℃、数均分子量Ｍｎ ＞ ３ ０００ 、陶瓷收率达７９ ％ （ 质量分数） 以上的陶瓷先驱体聚合物。该先驱体溶解性能好，并具有良好的纺丝性能。文中还利用ＩＲ、ＴＧ—ＤＴＡ 等手段对该先驱体的热解机理进行了初步探讨。

A high melting point polycarbosilane was prepared by changing synthetic time, pressure and temperature. Its melting point of the polycarbosilane obtained is more than 380℃, its average molecular weight is more than 3 000,and its ceramic yield can reach 79% by weight. The polycarbosilane precursor can dissolve in solvents such as xylene and tuloene, and its solution has a good spinnality. The primary pyrolysis mechanism of the polycarbosilane was explored by IR and TG-DTA technique.