The Preparation And Structure Performance Study Of Epoxy Resin/Graphite Conductive Composite Material

With the rapid development of science and technology, polymer materials, which have corrosion resistance, light quality, excellent processing performance and other advantages, are applied in a larger scope. At the same time, the demand of polymer conductive composite materials in electronic products has developed rapidly, and has been hailed as a more efficient, more economical and efficient polymer conductive material.This thesis aims to explore the effect of the processing technology of epoxy resin or graphite conductive composite material on the conductive properties of the composite, with epoxy resin substrate as its basis and lake graphite as conductive filler. In other words, it is to build a “dual percolation threshold” conductive network in the epoxy resin composites through preparing the masterbatch beforehand. Comparing with the traditional processing, this way can reduce the conductive percolation threshold of epoxy resin or graphite composite and improve the conductivity of the composite. In addition, the author analyzes the influence of the processing technology on the other properties of the composites by a series of characterization means.Meanwhile, since the epoxy resin is a thermosetting resin, the curing behavior and rheological properties in the processing process reflect the specific reaction process and crosslinking behavior in the resin system, which directly determines the physical and chemical properties of its product. So this thesis studies the effects of different heating rates on the characteristic temperature, curing reaction heat and exothermic peak temperature of the resin system by the non-isothermal DSC method. The apparent activation energy and reaction order of curing reaction are obtained by using Kissinger equation, Ozawa equation and Crane equation. Besides, the author makes a comparison of the influence of these two processing methods on the curing behavior of epoxy resin system. Through dynamic viscosity analysis method, the researcher finds the composite viscosity's dependence on temperature, and discovers the gelation temperature and the best processing temperature range of the sample. Besides, through constant temperature viscosity analysis method, the author finds the level of heating temperature, the content of graphite filler and the influence of processing technology on resin gelation time and rate of cure. The roller semi empirical equation and Arrhenius equation are adopted to get viscous flow activation energy and curing reaction activation energy, and analyze correspondingly the influence of traditional method and the method of masterbatch on epoxy resin rheological properties.