MDT苯基硅树脂的合成研究

Research on Synthesis of MDT Phenylvinyl Silicone Resin

以苯基三甲氧基硅烷(T型)、苯基甲基二甲氧基硅烷(D型)和1,1,3,3-四甲基-1,3-二乙烯基二硅氧烷(M型)为原料制得MDT苯基硅树脂。借助核磁(~1H NMR、^(29)Si NMR)、红外(FTIR)和紫外-可见光对MDT苯基硅树脂的结构进行表征分析。结果表明:水解缩合反应温度为55℃,催化剂盐酸质量分数为1.25%,反应溶剂甲苯与乙醇的质量比为2.5时,能得到无色透明的MDT苯基硅树脂,产率达84%;黏度和折射率随单体量之比(nT∶nD)的减小而增大。固化实验研究表明:MDT苯基硅树脂固化物的抗低温性能随nT∶nD的降低而提高,当n T∶nD>2时,MDT苯基硅树脂固化物具有良好的耐紫外光和抗高温老化性能。

A novel phenylvinyl silicone resin with M, D, and T groups, was prepared by cohydrolysis and polycondensation of phenyhrimethoxysilane （PTMS） , phenylvinylmethoxysilnae （ PMDS）, and 1,3 - divinyl - 1,1,3,3 - tetramenthyldisiloxnae as raw materials. The structure of MDT vinylphenylsilicone resins was char- acterized by H NMR, Si NMR, FTIR, UV -vis and MS -TOF. Results showed that under the condensation temperature of 55℃ and 1.25 wt% concentration of HC1, the yield of transparent and colorless MDT vinylphe- nylsilicone resins could reach up to 84% when the mass ratio of the solvents was toluene/ethanol = 5/2. The toughness of the materials originated from the cured MDT phenylvinyl silicon resins and hydrogen polyphenylsi- loxanes was improved with the decreasing of the ratio of T/D. The cured experiment indicated that the low temperature resistance was enhanced with the decreased of the ratio of T/D. and the cured MDT silicone resins exhibited an excellent UV -resistance and anti -aging properties when the ratio was more than 2.