Research On The Influence Of Carbon Materials On The Dieletric And Thermal Conductivity Of Natural Rubber

Natural rubber is a pure and natural polymer material with comprehensive properties.China is the largest rubber consumption country in the world,rubber will be vulcanized in the production process and consume and waste a lot of energy,then this problem will be effectively solved by microwave vulcanized rubber.At present,the research content of all sectors of society focuses on the research and development of microwave heating equipment.In order to analyze the influence of carbon materials on the dielectric properties and thermal conductivity of natural rubber,the following aspects are studied in this paper:1.Natural rubber was prepared mixed p with different amount of carbon blackp,graphenep and carbon nanotubep,then the dielectric parameters of the samples were measured and the influence of frequency,temperature,type of carbon materials and amount of carbon materials on the dielectric parameters were analyzed.2.Molecular dynamics was used to construct molecular models of different types and amounts of carbon materials and natural rubber,to predict the influence of different carbon materials and different amounts on the thermal conductivity of natural rubber.COMSOL was used to study the influence of interface thermal resistance and anisotropy on thermal conductivity.3.The COMSOL was used to simulate the temperature distribution of different carbon materials and natural rubber composite materials,as well as the effects of the real and imaginary parts of dielectric parameters,thermal conductivity,and rubber layers on the temperature distribution of the rubber body.4.The effect of different carbon materials on the thermal resistance of natural rubber was studied through experimental characterization.Using COMSOL,the effect of contact thermal resistance on the temperature distribution and temperature parameters of the rubber body was studied.Based on the above analysis,the following conclusions are drawn:(1)The real part of the complex dielectric constant of carbon black_natural rubber composites and graphene_natural rubber composites changed similarly at different frequencies.At the beginning,it slowly changed with increasing temperature and decreases rapidly when a certain temperature was reached;and the real part of carbon_natural rubber composite increased with the increasing of temperature.The imaginary part of complex dielectric constant of carbon black_natural rubber composites,graphene_natural rubber composites,carbon nanotubes_natural rubber composites increased with the increasing of temperature at the beginning,then reached a peak when a certain temperature and then decreased.(2)Through molecular dynamics simulation of the thermal conductivity of carbon materials and natural rubber,it can be seen that as the weight increased,the thermal conductivity of the composite material also increased;The effect of the interface thermal resistance and anisotropy on the thermal conductivity of the composite material was preliminarily studied by using COMSOL,it can be seen that it had a greater impact on the thermal conductivity of the composite material.(3)The temperature distribution of the composite material of carbon nanotubes and natural rubber was more uniform than that of the other two carbon materials.As the real part of the complex dielectric constant becomes larger,the main heating area of the film gradually approached the center and the film temperature distribution becomed more uneven.With the increase of the imaginary part of the complex dielectric constant,the main heating area had not changed,the effect of microwave heating was increasing,but the temperature distribution is more uneven.As the thermal conductivity increases,the temperature distribution of the film was more uniform.(4)Reducing the contact thermal resistance of nature rubber,graphene is superior to carbon nanotubes than carbon black.The existence of contact thermal resistance maked the temperature distribution of the microwave heating of the film become uneven,which will increase losses and waste energy.