Studies On The Preparation And Properties Of High Performance Polyphenylene Ether Thermal Conductive Composite Material

With the rapid development of industry and information technology,there has been an increasing demand for thermally conductive materials in recent years.Among them,polymer-based thermally conductive composite materials have become the focus in academia and industry because of their excellent properties such as easy processing,light in mass,corrosion resistance,low cost,and good toughness.In the field of thermal management research and application it has been formed a trend of"plastering steel/aluminum".As one of the five major engineering plastics,polyphenylene ether(PPO)has many outstanding properties.If the poor thermal conductivity of PPO could improve,the scope of application will be broaden.Firstly,this subject uses polyphenylene ether as the matrix resin,and uses polypropylene,polyamide 6,polystyrene,and high-impact polystyrene as modified resins to prepare a series of polyphenylene ether alloys.The study finds that the use of high-impact polystyrene as the modified resin has the least effect on the mechanical properties of polyphenylene ether.When the mass ratio of polyphenylene ether and high-impact polystyrene is 3:1,the mechanical properties of this polyphenylene ether alloy(MPPO)is almost consistent with polyphenylene ether.Besides,the melt index has been greatly improved(from 4.20 g·10min-1 to 15.11 g·10min-1),which can make the polyphenylene ether alloy have better performance while maintaining its mechanical properties and easy to prepare.Secondly,on the basis of the above research,polyphenylene ether thermal conductive composite materials were prepared by melt blending method,and the effect of different types of thermal conductive fillers on the thermal conductivity of polyphenylene ether/high impact polystyrene blend resin(MPPO)was investigated.The results show that graphite fillers are more suitable as thermally conductive filler,and the larger the particle size of the thermally conductive filler,the more beneficial it is to improve the thermal conductivity of the composite material.When adding 50 wt%of worm graphite to MPPO,the thermal conductivity of polyphenylene ether composite material can reach 1.06 W·m-1·K-1,but its mechanical properties are greatly reduced,that limits its application range.Finally,in order to prepare polyphenylene ether thermally conductive composite materials with better mechanical properties,thermal conductivity and processing performance,this paper uses MPPO as the matrix resin,modified modified graphene(Gn)or reductive oxidation(rGO)as thermal conductive filler,by the means of solution blending to prepared a series of polyphene ether thermally conductive composite materials.The results show that the performance of the composite material containing Gn significantly better than the composite material which contains rGO.There are three reasons account for this phenomenon:the first is rGO has too many structural defects,the second is the plate size of rGO is too small,and the third is due to the poor thermal stability of rGO.By modifying Gn could get a modified graphene(K-2-oGn),which effectively improves its compatibility with polyphenylene ether.When adds 5 wt%of K-2-oGn to MPPO,the thermal conductivity of MPPO/K-2-oGn composite could reach 0.934 W·m-1·K-1 while the mechanical properties are better at the same time(its tensile strength could reach 79.25 MPa and the impact strength is 7.66 kJ·m-2),and the processing performance is excellent(the melt index is 7.71 g·10min-1).In addition,using graphene(Gn)and carbon fiber(CF)as the synergy thermal conductive filler,which could better construct a three-dimensional thermal network path in the composite.Mhen adding little Gn and 2 wt%CF to MPPO,the thermal conductivity of MPPO/Gn/CF composite could increased to 1.12 W·m-1·K-1 while the mechanical properties are excellent(its tensile strength could reach 78.25 MPa and the impact strength is 8.26 kJ·m-2),and the processing performance is good(melt index 5.67 g·10min-1).That means MPPO/Gn/CF could meet the needs of industrial applications.This subject starts from the aspects of blending modification of polyphenylene ether,screening of thermally conductive filler types,improvement of preparation methods and modification of filler,it has comprehensive and systematic study on the preparation and properties of polyphenylene ether thermally conductive composite materials which endowed with theoretical value and practical application value.