乙烯基硅氮烷-巯基共聚物热裂解研究

Pyrolysis of Polysilazane Containing Vinyl-thiol Copolymer

采用红外(FTIR)、热失重,热分析以及质谱联用(TGA-DTA-MS)、X射线衍射仪(XDR)、能谱仪对紫外光固化乙烯基硅氮烷-巯基共聚体系的热裂解行为进行了分析和表征.结果表明:300～500℃为聚合物裂解反应的主要温度范围.裂解过程会逸出多种小分子气体,其中体系中的S元素可能主要是以H2S和SO2和噻吩类的形式逸出;最终质量保持率为55.3wt%;热裂解转化物表观密度出现先下降后上升的趋势,最终达到2.09g·cm-3;在保温2h的条件下,热裂解转化物在1400℃下生成少量Si3N4晶体,在1600℃下,热裂解转化物晶体质量组成为m(SiO2):m(Si3N4):m(SiC)=3:26:71,结晶度达到91.3%.

The pyrolysis of UV curable polysilazane containing vinyl-thiol copolymer has been analyzed and characterized by FTIR, TGA-DTA-MS, XRD and energy spectrometry. Thermal decomposition of the UV curable copolymer occurred from 300 to 500 ℃. Many different kinds of gas molecules evolved during the pyrolysis, in which S element escaped from the copolymer as H2S, SO2 and thiofuran, with the total weight loss being 44.7 wt%. The density of pyrolysate dropped down at the beginning of pyrolysis, then successively increased, and finally reached 2.09 g.cm^-3. Si3N4 crystal could be formed in the pyrolytic process at 1400 ℃ after 2 h and the crystalline degree could reach 91.3% at 1600 ℃ meanwhile. The quality ratio of the final product was m（SiO2） ： m（Si3N4） ： re（SiC）=3 ： 26 ： 71.