尚淑英* 马鹏飞 张玲 李钰婷
(物理与材料科学学院，河南师范大学，新乡，453007)
关键词：介电，压敏，复合材料，阈值
中图分类号：TM215.1 文献标识码：A
摘要：采用不同粒径亚微米镍粉与硅橡胶按质量比为 2:1，2.8:1进行配料， 经过特殊的制备方法，制备成镍/硅橡胶高分子复合材料，并主要研究了复合材料的压敏性能和介电性能。通过对材料做性能测试发现当用亚微米镍粉做导电填料时，复合材料具有优异的压敏性能:当仅对材料施加一个 200KPa 压强时，质量比为 2.8:1 的镍(400 纳米填料)/硅橡胶复合材料的电导率变化了 9 个数量级。 同时，材料的压敏性能会随着导电填料粒径的变化而发生变化。为了充分研究材料的电学性能，实验分别测量出在不同压强下材料的电导率、介电常数随频率的变化数据，研究发现:当频率和压强发生变化时，材料的电导率和介电常数也会发生变化，表现出不同的电荷输运机制。
The study of the piezoresistivity anddielectric behavior of Ni/silicone composite near the percolation threshold
SHANG Shu-ying,MA Peng-fei, ZHANG Ling, LI Yu-ting
(College of Physics and Materials Science, Henan Normal University,Xinxiang 453007, China)
Keywords: dielectric, piezoresistivity, composites, percolation threshold
Abstract: Aseries of nickel/silicone rubber composites with differentsubmicron filler diameter and Ni/silicone mass ratio 2:1, 2.8:1 were prepared.The dielectric permittivity and conductivity of the composites were studied. Itwas found that the composites show good piezoresistivity: the conductivityof the composites with mass ratio of nickel/silicone rubber under 2.8:1 (400nm diameter filler) changed 9 orders under a low pressure around 200 kPa. Furthermore,the piezoresistivity of the composites changed with the diameter of thefillers. In order to study the conductivity of the materials thoroughly, thefrequency dependence of the conductivity and the dielectric permittivity of thecomposites under different pressures were studied, which showed that theconductivity and dielectric permittivity of the composites changed withmeasuring frequencies and pressure ,presenting different charge transportmechanisms.