含铈聚硅氧烷的制备及其对甲基乙烯基硅橡胶性能的影响

Preparation of Polysiloxane Containing Cerium and Its Effect on Properties of MVQ

分别以α,ω-二羟基聚二甲基硅氧烷和八甲基环四硅氧烷与无水三氯化铈为主要原料制备含铈聚硅氧烷(PSC),研究其对甲基乙烯基硅橡胶(MVQ)性能的影响。结果表明:铈原子成功接到两种硅氧烷上,制得两种PSC;采用α,ω-二羟基聚二甲基硅氧烷制备的PSC可以提高MVQ的耐热老化性能,当其用量为5份时MVQ热老化前后的性能均较好;添加八甲基环四硅氧烷制备的PSC的MVQ物理性能和耐热老化性能优于添加α,ω-二羟基聚二甲基硅氧烷制备的PSC的MVQ;PSC可提高MVQ的热稳定性能,添加5份八甲基环四硅氧烷制备的PSC可使MVQ(二段硫化胶)最大分解速率温度提高122. 8℃;PSC在MVQ中分散性良好。

Polysiloxane containing cerium（PSC） was synthesized by using α,ω-dihydroxypolydimethylsiloxane or octamethylcyclotetrasiloxane,and anhydrous cerium trichloride as main raw materials,and the effect of PSC on the properties of MVQ was investigated. The results showed that,two kinds of PSC were successfully prepared by bonding cerium atom to siloxane. The PSC prepared from α,ω-dihydroxypolydimethylsiloxane could improve the heat aging resistance of silicone rubber. When 5 phr PSC was used,the performances of MVQ before and after thermal aging were good. The physical properties and heat aging resistance of MVQ with PSC prepared by octamethylcyclotetrasiloxane were superior to those of MVQ adding PSC prepared by α,ω-dihydroxy-polydimethylsiloxane. PSC could be well dispersed in MVQ and improve the thermal stability of MVQ. With 5 phr PSC prepared by octamethylcyclotetrasiloxane,the temperature at the maximum decomposition rate of MVQ（twostage cured vulcanizate） increased by 122.8 ℃.