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研究了炭黑（ＣＢ）浓度、热历史和辐照对ＰＶＤＦ／ＣＢ复合物电阻行为的影响。结果表明，最大ＰＴＣ强度发生在临界浓度Φｃ处，Φｃ略大于渗流阈值Φｐ，渗流区以外基本无ＰＴＣ效应。热处理对电阻率－温度行为的影响由结晶状态（结晶度和结晶形态）造成的。结晶形态愈复杂，临界温度以下的正温度系数效应愈明显。结晶度越大，ＰＴＣ强度越大。并用ＤＳＣ测试结果解释了这一现象，４０Ｍｒａｄ以下剂量γ－６０Ｃｏ辐照能削弱ＮＴＣ效应，但不能完全消除。
The effects of carbon black (CB) concentration, thermal history and irradiation on the electrical resistance of PVDF / CB composites were investigated. The results show that the maximum PTC intensity occurs at the critical concentration Φc, Φc is slightly larger than the percolation threshold Φp, and there is almost no PTC effect beyond the seepage area. The effect of heat treatment on the resistivity-temperature behavior is caused by the crystalline state (crystallinity and crystalline morphology). The more complex the crystalline morphology, the more obvious the positive temperature coefficient effect below the critical temperature. The greater the crystallinity, the greater the PTC strength. This phenomenon was explained by the DSC test results. Γ-60Co irradiation at doses below 40 Mrad could weaken the NTC effect but could not be completely eliminated.