Preparation And Properties Of Conductive Composites

With the rapid development of electrical industry and communication technology, the demand of conductive polymer materials is more and more urgently. In this paper we introduce the sorts of the conductive polymer materials in detailed, sum up the preparation techniques and application situations of inherently conductive polymer and conductive polymer composites. At the same time, we also introduce the sorts and properities of conductive fillers of conductive polymer composites.By pretreatmenting with (CH₂)₆N₄, not only the heat-endurance of polymer matrix is enhanced, but also the process and molding technics performance of materials is improved. By analysing the solidification process of the polymer matrix using DSC,TGA methods, we ascertain the proper molding technics and prepare conductive polymer composites with modified GX resin as polymer matrix, glass fabrie cloth as tough material and ECA cabon black as conductive filler. The relations between electrical and mechanics performance and cabon black content are researched. When cabon black content is 3%(wt), samples' heating temperature reach 250°C under secure voltage and they have good mechanics performance too.Combining the theory and knowledge which have existed we analyse and discuss the conductive mechanism of conductive polymer composite samples and we believe that there are three kinds of conductive mechanism:electric conduction channel effectN tunneling effect and electric field emission effect at the same time when samples electric-conduct. The U - I characteristic of conductive polymer composites is studied. We find it has nonlinear relationship.Specilly when the voltage is higher, the nonlinear relationship is obvious. The reason is tunneling effect and electric field emission effect become stronger at higher voltage. It results U -I characteristic deviates linear relationship. The resistance-temperature coefficient effect is also studied. We find the samples have faint positive temperature coefficient effect. The reason is ascribed to the destruction of the conductive networks whoseingredients' volumes expand at high temperature.The conductive polymer composite samples we have prepared have good electrical and mechanics performance. They are easy to process and mold. Their electrical and mechanics performance can be adjusted in large scale according the requirement. So they have the wide prospect.