摘要
以对二溴苯为起始原料,在超声辐照下制备得到对二溴苯双格氏试剂,然后与二甲基氢氯硅烷制备得到1,4-双(二甲基硅基)苯)(BDSB)。以B(C6F5)3为催化剂,BDSB与二甲基二甲氧基硅烷缩聚制备得到聚(四甲基对硅亚苯基-二甲基)硅氧烷共聚物(PTMPS-DMS),并对催化剂浓度、反应温度对反应速率的影响进行了研究。29SiNMR表明产物不是严格交替共聚物,具有38%～49%的嵌段结构。PTMPS-DMS的Tg=-56.2℃,起始降解温度氮气、空气中分别为334℃、345℃。在氮气中PTMPS-DMS出现一步热失重,最大热失重温度是529℃,在空气中则分别在539℃、559℃、662℃出现多步热失重。
Grignard reagent was prepared under ultrasonic radiation with 1, 4-dibromobenzene as start material. The Grignard reagent then reacted with dimethylchlorosilane to form 1, 4-bis （dimethylsilyl） benzene （BDSB） . Poly （tetramethyl-p-silylphenylene-dimethyl） siloxane was prepared by the polycondensation of BDSB and dimethyldimethoxysilane catalyzed by B（C6F5）3, the effect of B（C6F5）3 concentration and reaction temperature on the reaction rate was also studied as well. 29Si NMR shows that the polymer is not perfectly alternated with 38-49% randomization. The Tg of the polymer is —- 56.2℃. The polymer begins to degrade at 334℃ in nitrogen and 345℃ in air. The polymer shows one-step weight loss in nitrogen at 529℃, but multi-step weight loss in air at 539, 559, 662℃.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2007年第9期1333-1337,共5页
Chemical Industry and Engineering Progress
关键词
苯撑聚硅氧烷
耐高温
弹性体
缩聚反应
poly （silphenylene-siloxane） s
high temperature materials
elastomer
polycondensation
