Electrical Properties of Polypropylene-Based Composites Controlled by Multilayered Distribution of Conductive Particles
Electrical Properties of Polypropylene-Based Composites Controlled by Multilayered Distribution of Conductive Particles
复制标题
导电颗粒多层分布控制聚丙烯基复合材料的电性能
DOI：
10.1021/am506773c
复制
发表时间：
2015-01-28
影响因子：
9.5
通讯作者：
Guo, Shaoyun
中科院分区：
文献类型：
--
作者：
Gao, Wanli;Zheng, Yu;Guo, Shaoyun
制备了由纯聚丙烯（PP）和炭黑填充聚丙烯（PPCB）交替层组成的材料。从两个方向研究了多层复合材料的电学行为：(1)平行于界面方向。有限的层空间允许CB颗粒之间更紧密的连接，而随着层数的增加，导电途径往往会被破坏，导致由于绝缘PP层的分离而导致电阻率的明显增强。(2)垂直于接口。绝缘层和导电层的交替组合就像一个平行板电容器，使得电导率变得依赖于频率。在层倍增过程中，由于界面处电荷的积累，介质介电常数显著增强。因此，当微波入射到介电介质上时，界面极化是微波能量固有耗散的主要贡献，因此，随着材料层数的增加，吸收峰增强。此外，多层体系中的层界面也有效地抑制了拉伸过程中裂纹的扩展，导致断裂伸长率高于PP/CB常规体系，这为制造具有最佳力学性能的电气材料提供了潜在的途径。
Materials consisting of alternating layers of pure polypropylene (PP) and carbon black filled polypropylene (PPCB) were fabricated in this work. The electrical behaviors of the multilayered composites were investigated from two directions: (1) Parallel to interfaces. The confined layer space allowed for a more compact connection between CB particles, while the conductive pathways tended to be broken up with increasing number of layers leading to a distinct enhancement of the electrical resistivity due to the separation of insulated PP layers. (2) Vertical to interfaces. The alternating assemblies of insulated and conductive layers like a parallel-plate capacitor made the electrical conductivity become frequency dependent. Following the layer multiplication process, the dielectric permittivity was significantly enhanced due to the accumulation of electrical charges at interfaces. Thus, as a microwave was incident on the dielectric medium, the interfacial polarization made the main contribution to inherent dissipation of microwave energy, so that the absorbing peak became strengthened when the material had more layers. Furthermore, the layer interfaces in the multilayered system were also effective to inhibit the propagation of cracks in the stretching process, leading to a larger elongation at the break than that of the PP/CB conventional system, which provided a potential route to fabricate electrical materials with optimal mechanical properties.