导电炭黑填充PP-EAA复合材料的形态及电性能

以聚丙烯(PP) 和乙烯-丙烯酸共聚物( EAA) 的共混物为基体材料, 以导电炭黑为填料, 通过熔融共混的方法制备了导电复合材料。探讨了导电炭黑在两相基体中的分散情况以及聚丙烯结晶度对复合体系导电性能的影响。扫描电镜测试结果表明, 在共混物中炭黑粒子选择性分散在极性EAA 树脂中, 同时EAA 树脂在聚丙烯基体中形成连续网络结构, 从而显著降低了复合体系的渗滤阈值。电性能测试结果表明, 材料在相同导电炭黑含量下的体积电阻率相对于单基体体系有7～8 个数量级的降低, 并且结晶度较高的PP 更有利于降低复合体系的体积电阻率。此外, 炭黑/ PP-EAA 复合材料的拉伸强度相对于炭黑/ PP 体系有所下降, 而断裂伸长率有所提高。 

Morphology and conductivity of conductive carbon black f illed PP-EAA composites

The conductive composites based on conductive carbon black (CB) , polypropylene ( PP) and poly (ethylene-co-acrylate) ( EAA) were prepared via the melt blending. The dispersion of CB in the two-phase mat rix and theeffect of crystallinity of PP on the conductivity of the composites were discussed. SEM observation indicates that theCB particles were selectively located in the polar EAA resin , which formed a continuous network st ructure in the PPmat rix , resulting in a great decrease of the conductive percolation threshold of the composites. The elect rical testingresult s indicate that compared to the CB/ PP system , the volume resistivity of CB/ PP-EAA composites decreases by7～8 orders of magnitude at the same filler content . PP with higher crystallinity is more favorable for decreasing thevolume resistivity of the composites. Furthermore , the tensile st rength of CB/ PP-EAA composite decreases somewhat compared to the CB/ PP system , while the elongation at break increases.