制备了一种以氟碳树脂为基体,聚丙烯腈(PAN)基短切碳化纤维为导电填料的抗静电复合涂层。讨论了纤维的含量、长度、涂层厚度及外加电压对涂层表面电阻率的影响。结果表明表面电阻率和碳化纤维质量分数之间的关系符合逾渗理论,当纤维长度为4mm时,此体系的渗滤阈值为2.5‰(质量分数),其表面电阻率为10^6Ω,具有良好的抗静电性能;表面电阻率随纤维长度的增加而降低,但降低的程度愈来愈小;涂层厚度在不超过134μm的情况下,对表面电阻率的影响较小;涂层的表面电阻率在高外加电压下较低外加电压下小;碳化纤维/氟碳树脂复合涂层的导电机理是由导电通道、隧道效应和场致发射3种导电机理竞相作用的结果。
A kind of antistatic coating was prepared with fluorocarbon resin as matrix, polyacrylonitrile (PAN)- based short carbonaceous fibers as conductive filler. The influences of fiber content, fiber length, coating thick- ness and applied voltage on the surface resistivity were discussed. The results show that the relationship be- tween surface resistivity and mass fraction of carbonaceous fiber was suitable for percolation theory, and the percolation threshold is 2.5wt‰ when the length was 4mm; the coating has a surface resistivity of about 10^6Ω, and have a good antistatic function; surface resistivity decreases with increasing fiber length, but the extent ta- per off gradually; and yet, the thickness which is less than 134μm has little impact on it; surface resistivity was smaller in high applied voltage compared with low voltage. The conductive mechanism of the coating mainly de- pends on conductive path theory, tunneling effect and field mission.