摘要
V2O3粉末为填料聚乙烯(PE)及环氧树脂(EPOXY)为基体的复合型导电高分子材料电阻随温度的变化具有低温(-100℃)NTC效应和高温PTC效应.低温NTC源于V2O3相变导致的电阻下降,高温PTC源于填料和基体的复合效应:即基体膨胀引起填料导电网络开断.PTC转变温度接近基体熔点(Tm)或玻璃化温度(Tg).填料体积分数略大于临界体积分数时,PTC转变温度较远地低于Tm或Tg,更换基体能改变PTC转变温度.PTC转变后出现高温NTC,它产生于高温基体软化填料导电网络的自修复.
Conductive polymer composites have been made by incorporating V2O3 powder into polymermatrices.The composites show a special resistivity and temperature relationship including lowtemperature(- 100℃ )NTC and high temperature PTC.the NTC is the result from phase transitionof V2O3.The PTC can be attributed to the fact that matrix dilation breaks conductive networkcomposed by filler particles.PTC trasition temperature is that negstively approaching Tm or Tg. Hightemperature NTC after PTC were detected and it could be explained by the possible self revision ofconductive network.