乙炔炭黑填充VMQ／EPDM共混导电橡胶的流变性能和结构分析

Rheological Properties and Structure Analysis of VMQ/EPDM Conductive Blends Filled with Acetylene Carbon Black

用孟山都流交仪测定了不同共混比的甲基乙烯基硅橡胶（ＶＭＱ）／ＥＰＤＭ共混混炼胶的流变性能；用网笼法测定了炭黑在共混体系两相中的比例；研究了薄通次数对共混硫化胶体积电阻率的影响；用透射电镜观察了硫化胶的形态。根据试验结果得出：适当并用比和炭黑填充量的ＶＭＱ／ＥＰＤＭ共混硫化胶具有高导电性的原因是：两相粘度相差较大，共混体系为明显的“海－岛”结构，而且炭黑在共混体系两相中的浓度不同；具有高导电性及其加工稳定性的ＶＭＱ／ＥＰＤＭ共混导电橡胶的最佳并用比例为８０／２０—７０／３０。

The rheological properties of VMQ/EPDM compounds with different blending ratio were determined by Monsanto rheometer; the proportions of carbon black in two phases of blends were determined by net-cage extraction; the influence of mill run number on the bulk resistance of blend vulcanizates was investigated; the morphology of vulcanizates was studied by TEM. The results showed that the VMQ/EPDM vulcanizates with proper blending ratio and carbon black level possessed high conductivity because of their obvious 'sea-island' structure with quite different viscosity and carbon black proportion in two phases of blends;the VMQ/EPDM blends with a blending ratio of 80/20-70/30 showed the optimum conductivity and processibility.