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研究了炭黑／聚乙烯导电复合材料的ＰＴＣ特性及在不同条件下的电阻变化。发现ＰＴＣ特性与体积膨胀及聚乙烯晶相的熔融有许多一致性。认为材料的体积膨胀及聚乙烯晶相熔融时炭黑颗粒均匀化扩散导致了电阻随温度上升。在较高温度下，炭黑颗粒在分子链段热运动的推动下会发生相对聚集使电阻不断减小，这是材料出现ＮＴＣ现象的原因。材料总的电阻温度特性是体积膨胀、炭黑向聚乙烯熔融区扩散及相互聚集三个因素共同作用的结果。
The PTC characteristics of carbon black / polyethylene conductive composites and their resistance changes under different conditions were studied. The PTC properties were found to be in many agreement with the volume expansion and melting of the polyethylene crystalline phase. It is considered that the resistance increases with temperature due to the volume expansion of the material and the homogenization and diffusion of the carbon black particles when the polyethylene crystal phase is melted. At higher temperatures, the relative aggregation of carbon black particles, driven by the thermal movement of the molecular chain segment, leads to a decrease in resistance, which is responsible for the NTC phenomenon in the material. The total temperature resistance of the material is the result of the combined effect of volume expansion, diffusion of carbon black into the polyethylene melt zone, and aggregation with each other.