Investigations On The Preparation And Properties Of Polyphenylene Oxide Based Microwave Dielectric Composites With High Frequency And Low Loss

With the development of communication technology,it has now reached the 5G communication era.In the field of 5G communication,polymer matrix composites(PMCs)prepared with a microwave dielectric ceramics as fillers are used in base stations(micro base stations)or terminals as dielectric antennas used with substrates,etc.,it has been widely concerned by scientific research institutions and industries at international.Polyphenylene oxide(PPO)resin has excellent characteristics such as ultra-low dielectric loss,excellent mechanical properties,and easily molding,which makes PPO resin as an excellent choice as a polymer matrix in PCMs.In this paper,HIPS with PPO to make alloys,surface modification of Ca_0.7La_0.2Ti O₃-Mg Ti O₃(CLTMT)ceramics powder with KH560 and the influence of particle size of CLTMT ceramics powder on the properties of PMCs are studied.(1)Although PPO has excellent dielectric and mechanical properties,its application is limited due to its shortcomings that it is difficult to process and shape.In previous studies,PPO resin is generally modified to improve its processing performance.In the preview researcher,polystyrene(PS)and its derivatives,like high impact polystyrene(HIPS)is a common method of physical modification.However,little research has been done on the alloys dielectric properties.In this article,I have mechanically blended HIPS and PPO with different ratios and studied its performance.Finally,I came to the conclusion that when the ratio of PPO to HIPS is 2:1,the performance of the prepared alloy shows the best properties.Which the dielectric constant is 2.54 with dielectric loss is 1.38×10^-3,the thermal expansion coefficient is 72.3ppm/?,and the bending strength reaches 73.00MPa.And maintains excellent thermal stability.The alloy prepared with this ratio will be named m PPO as the matrix of the composite material.(2)Using 0.5wt.%KH560 of CLTMT ceramics with the particle size of 4?m to prepare composite materials with m PPO after surface modification of CLTMT ceramics,and comparing the comprehensive performance of composite materials before and after modification,it can be concluded that KH560 can effectively Improve the organic/inorganic interface and improve the overall performance of the composite material.When the filling ratio of the modified CLTMT ceramic is 20vol.%,the PCMs shows excellent overall performance,with the dielectric constant of 4.24 with dielectric loss of 1.32×10^-3,the thermal expansion coefficient reaches 56.91ppm/?,and the flexural strength is 111.4MPa.(3)Comparing the performance of composite materials using CLTMT ceramic powder with particle size of 15?m(CLTMT-15)and 4?m(CLTMT-4)as a filler,it is found that when CLTMT-15 is used as filler,the composites can obtain more excellent performance.Comprehensive performance.When the filler content of CLTMT-15 is40vol.%,the composite shows the best overall performance,with a dielectric constant of 6.81,a dielectric loss of 1.04×10^-3,the thermal expansion coefficient of 25.27ppm/?,and the bending strength of 110.4MPa.