具有隔离结构的聚丙烯/碳纳米管复合材料的制备及电磁屏蔽性能

通过共挤出包覆-热压法制备了具有隔离结构的聚丙烯(PP)/碳纳米管(CNTs)电磁屏蔽复合材料。 其中,CNTs随机分布于PP基体中形成导电相,该导电复合物作为包覆层包敷在纯PP颗粒表面,形成包覆复合粒子,经热压后形成隔离导电网络。 结果表明,所制备的隔离结构复合材料呈现良好的导电性能,可获得较低的导电逾渗值0.28%(体积分数);在CNTs质量分数为5.6%时,该复合材料电磁屏蔽性能达到25.6 dB,同时具有良好的力学性能。 本文结果表明,共挤出包覆-热压法制备隔离结构导电复合材料方法简单可控、绿色环保,对开发高性能电磁屏蔽复合材料具有重要指导意义。

Preparation and Electromagnetic Shielding Properties of Polypropylene/Carbon Nanotubes Composites with Segregated Structure

Constructing segregated structure in polypropylene (PP)/carbon nanotubes (CNTs) composites via co-extrusion coating-compression molding technique is an effective way to achieve high electromagnetic interference shielding with low percolation threshold. Among them, CNTs are randomly distributed inside PP matrix to form conductive composites, which is coated on the outer surface of pure PP to form a segregated structure. The results show that the PP/CNTs composites exhibit an excellent electromagnetic interference shielding effectiveness (EMI SE) of 25.6 dB at 5.6% (mass fraction) of CNTs, and high-performance electrical conductivity with a low percolation threshold of 0.28% (volume fraction) CNTs. Furthermore the PP/CNTs composites have excellent mechanical properties. In a word, the co-extrusion coating-compression molding technique is a facile and green method, which plays a role in developing high-performance electromagnetic shielding composites.