新型聚甲基甲氧基硅氧烷交联剂对硅橡胶性能的影响

Properties of siloxane elastomer crosslinked by polymethylmethoxylsiloxane

以聚甲基甲氧基硅氧烷(PMOS)作为交联剂,将端羟基聚二甲基硅氧烷(PDMS)在室温下交联固化生成硅橡胶,并研究了PMOS对硅橡胶固化性能与力学性能的影响。计算表明,固化反应的表观活化能为3.92kJ/mol,IR测试表征了体系固化前后官能团的变化。硅橡胶的密度随PMOS含量的提高而增大。与传统交联剂相比,PMOS可以原位形成一种高交联密度的PMOS相,这种PMOS相对硅橡胶有显著地增强作用,当PMOS含量由15%增加到47%时,硅橡胶的模量增加3倍,断裂伸长率减小一半。PMOS可作为硅橡胶的新型室温增强交联剂。

Polymethylmethoxylsiloxane （PMOS） with dense pendant silicone-methoxy groups was used as crosslinking reagent for room temperature vulcanized polydimethylsiloxane （PDMS）. The apparent activation energy for crosslink reaction was 3.92kJ/mol. The crosslink density increased as the formation of PMOS dense phases. It was detected that these PMOS phases improved the mechanical properties of siloxane elastomer significantly. Elastic module increased three times and the elongation at break felled a half, when the PMOS content increased from 15% to 41%. PMOS could be used as room temperature enhancing crosslinker for silicone elastomer.