氟硅共聚生胶的合成及结构分析

以1,3,5-三(3,3,3-三氟丙基)-1,3,5-三甲基环三硅氧烷(D3F)和六甲基环三硅氧烷为原料合成了高分子量的氟硅共聚生胶,研究了反应时间和反应温度对产物分子量的影响,以及单体投料比对共聚物链节含量的影响.通过红外光谱和核磁共振波谱对共聚生胶的结构进行了表征,并用乌氏黏度计测定了其分子量.结果表明,在D3F用...

Synthesis and structure analysis of fluorosilicone copolymer raw rubber

1,3,5-tris（3,3,3-trifluoropyl）-1,3,5-trimethylcyclotrisiloxane （D3F） and hexamethylcyclotrisiloxane were used as raw materials to synthesize fluorosilicone copolymer with high molecular weight. The effects of reaction time and reaction temperature on molecular weight of the products and monomer ratio on chain segment content of the copolymers were studied. The structure of the copolymer was characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy, and its molecular weight was determined by Ubbelohde viscometer. The results showed that the proportion of chain segment content in fluorosilicone rubber was closer to that of feed when D3F amount was high. With increase of reaction temperature and time, molecular weight of the fluorosilicone copolymer first increased and then decreased. Molecular weight of fluorosilicone copolymer could be effectively increased by stopping heating at an approp-riate node in the reaction process. When the reaction temperature was 90 ℃, reaction time was 10 min and mole fraction of D3F was 80%, molecular weight of fluorosilicone copolymer reached the maximum, and the viscosity average molecular weight was 8.2×105.