【摘要】 用四针状ZnOw作为导电填料制备了电阻率为 10 6～10 10 Ω的导电或半导电聚氨酯 /ZnOw、聚氯乙烯 /ZnOw和天然橡胶 /ZnOw复合材料 ,对其表面电阻和体积电阻进行了测试和分析。结果表明 ,四针状氧化锌晶须可以高效地降低高分子材料的电阻。通过分析和计算提出了树脂基 /ZnOw复合材料导电通道形成所需四针状氧化锌晶须的临界体积含量υc。对上述体系的导电机理分析结果表明 ,外电场作用下 ,复合体系中晶须针尖产生的电荷集中为普通球形粒子的 40 0倍以上 ;当晶须间距离很小时 ,可能由于隧道效应产生漏电流而提高导电性更多还原

【Abstract】 Composites of polyurethane/ZnOw, polyvinyl/ZnOw and natural rubber/ZnOw with the electrical resistivity of 10 6 to 10 10 Ω were prepared using tetrapod shaped zinc oxide whisker as the conductive additives. The conductive behavior of this system has been analyzed and the results show that the tetrapod shaped ZnOw is an effective additive for lowering the electrical resistivity of polymer materials. A formula of critical volume fraction of ZnOw for the formation of the conductive nets of the polymer/ZnOw composite has been put forward and compared with the experimented results. The analysis of the comductive mechanism indicates that the charge concentrating effect at the needles’ tips of the whisker will be distinct if the material under an electric field. The tunnel effect may exist and cause leakage current in this kind of composites.更多还原