高相对分子质量氟硅生胶的制备与热性能研究

Research on Preparation and Thermal Properties of High Molecular Weight Fluorosilicone Rubber

以γ-三氟丙基甲基环三硅氧烷(D3F)、三甲基三乙烯基环四硅氧烷(D3Vi)为原料,碱为催化剂制得了乙烯基质量分数为0.25%、不同相对分子质量的氟硅橡胶。采用D3Vi作为共聚单体可以将乙烯基引入到共聚物中,实验中D3F的聚合速率非常高,10 min后的转化率均为90%以上。优化了聚合反应条件,通过FTIR、1H-NMR、GPC表征了氟硅生胶的结构组成和相对分子质量,通过DSC和TG研究了其热性能。结果表明,氟硅生胶的玻璃化转变温度为-69℃,在300℃以下未出现明显的热降解现象,耐高温性能低于普通的甲基乙烯基硅橡胶。

A series of fluorosilicone rubber with 0.25% vinyl content and different relative molecular mass was prepared with 1,3,5-Tris[(3,3,3-trifluoropropyl)methyl]cyclotrisiloxane(D3F) and 1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane(D3Vi) as raw materials, and alkali as catalyzer. D3Vicould bring vinyl group into the copolymer, and the polymerization rate of D3F was very high, the monomer conversion achieved more than 90 percent in ten minutes. The study optimized polymerization conditions, the structure and relative molecular mass of polymers were investigated by FTIR,1H-NMR, GPC, and the thermal performance was studied through DSC and TG. The results suggested that the glass transition temperatures of fluosilicone rubber was-69 ℃, and it did not reveal significant thermal degradation phenomena in the less than 300 ℃, the high-temperature resistance was lower than general methyl vinyl silicone rubber.