镀Ag玻璃微珠-膨胀石墨/聚氯乙烯导电复合材料的制备与表征

摘要

Electroless Ag plating was performed on surface of hollow glass beads (HGB)using a Pd-free and SnCl2 free electroless Ag plating new process,then electroless Ag plating on glass beads (Ag-GB)-expanded graphite (EG)/poly(vinyl chloride)(PVC)composites were prepared by melt blending method.Surface morphology and structure of Ag-GB coating were characterized by SEM,EDS and XRD test methods.And the effects of Ag-GB and EG as composite fillers on the electrical conductive and mechanical properties of Ag-GB-EG/PVC composites were also investigated.The results show that the surface of pretreated HGB result in Ag layer deposition easily,the coat-ing is more uniform and compact,and the mass fraction of Ag layer on the Ag-GB surface is 81.15%.When the mass fraction of Ag-GB is fixed to 1 5%,with the increase of EG mass fraction,the volume resistivity of the Ag-GB (1 5%)-EG/PVC composites decreases nonlinearly.When the mass fraction of EG is about 1 2%,which reaches the percolation concentration,whose volume resistivity is 2.18×103 Ω·cm,meeting application requirement for anti-static PVC materials.Furthermore,when the mass fraction of EG is 1 2%,the volume resistivity of the Ag-GB (15%)-EG/PVC composites is equivalent to that of the Ag-GB(50%)/PVC composites,and the tensile strength of the Ag-GB(1 5%)-EG/PVC composites reaches the maximal value.%采用一种无Pd无 SnCl2化学镀 Ag新工艺对空心玻璃微珠(HGB)表面进行化学镀 Ag,然后通过熔融共混方法制备镀 Ag玻璃微珠(Ag-GB)-膨胀石墨(EG)/聚氯乙烯(PVC)复合材料。借助 SEM、EDS和 XRD测试手段对Ag-GB镀层的表面形貌与结构进行了表征,研究了Ag-GB和EG作为复合填料对Ag-GB-EG/PVC复合材料导电和力学性能的影响。结果表明：预处理的 H GB的表面更易于 Ag 层的沉积,镀覆的镀层更为均匀、致密；Ag-GB表面的 Ag层质量分数为81.15%；固定 Ag-GB 的质量分数为15%,随着 EG 质量分数的增加,Ag-GB (15%)-EG/PVC复合材料的体积电阻率呈非线性降低趋势,当 EG 的质量分数达到逾渗阈值12%时,Ag-GB (15%)-EG/PVC复合材料的体积电阻率为2.18×103Ω·cm,满足抗静电 PVC材料的应用要求。添加质量分数为12%的 EG,Ag-GB(15%)-EG/PVC复合材料的体积电阻率与单独填充质量分数为50%的 Ag-GB时 Ag-GB/PVC复合材料的体积电阻率相当,此时其拉伸强度达到最大值。