Preparation And Properties Of G-C₃N₄/Thermally Conductive Particles/MVQ Composites Material

With the development of science and technology,the market for functional materials and investment in scientific research have developed extremely rapidly,and as a supplement to metal and ceramic thermal conductive materials,polymer-based thermal conductive composite materials have extremely great development potential,the simple addition of polymers in the past,However,the physical and chemical properties of composite are poor due to simply adding heat conducting materials to the polymer,so its application scope and market are greatly limited.In order to solve the problem of coMPatibility,the quasi graphite phase carbon nitride（g-C₃N₄）was used to load the common heat conduction,the g-C₃N₄ was used as the intermediate medium to contact polymer and heat conducting filler respectively.Polymer-based composites are prepared using the following methods.Firstly,high pressure synthesis and melamine（C₃H₆N₆）was used to prepare high purity g-C₃N₄ in semi-closed environment,Secondly,three common thermal conductive fillers,copper particle（Cu）,aluminum particle（Al）and zinc oxide particle（ZnO）are loaded on the g-C₃N₄ template,and then three kinds of composite fillers Cu/g-C₃N₄,Al/g-C₃N₄ and ZnO/g-C₃N₄ were obtained Finally,polymer-based composites were obtained by using basic thermal conductive fillers and prepared composite fillers to fill methyl vinyl silicone rubber（MVQ）,respectively.The structure and composition of composite filler were analyzed and determined by testing its micro morphology,physical structure,chemical structure and element proportion.And then,the mechanical properties,micro morphology,chemical structure,thermal stability and thermal conductivity of the polymer-based composites were tested and characterized.The results show that there are three kinds of loading forms between g-C₃N₄ and conductive particles.Composite particles are formed by forming network structure and wrapping Cu when Cu is loaded by g-C₃N₄;The loading of Al on g-C₃N₄ is through adhesion of g-C₃N₄ and Al to form composite particles;The composite particles of g-C₃N₄ loaded ZnO is formed by ZnO adhering to the particles with g-C₃N₄ as the core.In addition to,the mechanical strength of composite can be improved obviously due to g-C₃N₄ have better coMPatibility than others heat conduction filler.The improvement of Cu by g-C₃N₄ is the most obvious,however,the thermal conductivity of composite decreases slightly due to its barrier effect,.Although g-C₃N₄ loaded with thermal conductive particles cannot improve the initial decomposition temperature of composite,it can significantly delay the decomposition speed of composite.In addition,it hinders the dispersion and combination of composite filler in polymer due to the particle size of thermal conductive composite filler is too large.Finally,the mechanical strength of the composite after tearing is reduced.