抗静电剂对软质聚氯乙烯电学性能的影响

摘要

在聚氯乙烯(PVC)/邻苯二甲酸二辛酯(DOP)中加入抗静电剂SAS93、抗静电剂SN、导电炭黑、乙炔炭黑等助剂,采用熔融共混法制备了抗静电软质PVC片材;采用万能试验机、高绝缘电阻测量仪、场发射扫描电子显微镜研究了抗静电剂种类和组分对PVC片材的力学性能、体积电阻、表面电阻及形貌的影响.结果表明,添加0.5份的抗静电剂SAS93或SN均可使复合材料的体积电阻和表面电阻快速下降到107～108 Ω;与SAS93相比,SN对软质PVC的硬度影响基本一致,SN对复合材料的拉伸性能影响更大;在软质PVC中添加20份的乙炔炭黑或导电炭黑时才能达到体积电阻和表面电阻为107～108 Ω的效果;在添加30份乙炔炭黑或导电炭黑时,软质PVC的体积电阻和表面电阻下降到103～104 Ω;添加20份乙炔炭黑或导电炭黑时,复合材料的表面电阻和体积电阻发生突变,即该炭黑的逾渗阈值为20份.%The soft poly (vinyl chloride) (PVC) compounds containing dioctyl phthalate were prepared by melt blending with an antistatic agent (SAS93),an antistatic agent (SN),conductive carbon black and acetylene black.The mechanical properties,volume resistance,surface resistance and morphology of these compounds were evaluated.The results indicated that the volume and surface electrical resistance was reduced to 107 ～10a Ω when 0.5 phr SAS93 or SN was added into PVC.The antistatic agent SN had the same effect on the stiffness of PVC compounds with SAS93,but it exhibited a more significant effect on tensile properties.On the other hand,the addition of 20 phr conductive carbon black or acetylene black into PVC led to the volume and surface electrical resistance of 107 ～108 Ω,which could be further reduced to 103～104 Ω with the addition of 30 phr carbon black.It was deduced that the percolation threshold of carbon black for PVC was 20 phr.