具有“沙袋”结构的PP/EPDM/CB导电复合材料的形态构建及性能研究

提出通过构建类似拳击训练沙袋的硬核-软壳分散相结构来同时实现导电高分子复合材料的高电导率和高韧性这一设想，并通过两步熔融共混法构建了这种具有“沙袋”分散相结构的聚丙烯（PP）/三元乙丙橡胶（EPDM）/炭黑（CB）导电复合材料，其中，CB粒子选择性分布于EPDM分散相中。通过定量计算发现，无论从热力学角度还是动力学角度，CB粒子均倾向于选择性分布在EPDM中，这也阐明了“沙袋”分散相结构的形成机理。此外，性能测试表明，这种具有“沙袋”分散相结构的导电复合材料的体积电导率和缺口冲击强度随炭黑含量的增加呈现反常的同步增长。

Morphology Construction and Properties of the Conductive PP/EPDM/CB Composite with Sandbag Structure

In this paper, a boxing sandbag liked hard core-soft skin structure was proposed for a filled conductive polymer composite with both high conductivity and toughness. Via a two-step method, a polypropylene/ethylene propylene diene monomer/carbon black (PP/EPDM/CB) ternary composite with a sandbag structure was prepared, in which PP constituted the continuous phase and EPDM the dispersed phase with CB particles selectively distributed in EPDM. Quantitative calculation confirmed that CB preferably distributed in EPDM for both dynamical and thermodynamical reasons, which provided the mechanism of the formation of “sandbag” microstructure. It was found that the volume conductivity and notched impact strength increased simultaneously with increasing CB loading.