Coupling agent modified MGSA ceramic powder filled PTFE composite materials: High thermal conductivity and low dielectric loss of substrate materials for microwave high frequency and high-speed communication

Polymer-ceramic composite substrates have been widely focused and used in recent years due to the 5th generation high frequency and high-speed communication. C 9 H 14 O 3 Si (Z6124) modified Mg 1.99 Ga 0.01 Si 0.99 Al 0.01 O 4 (MGSA) ceramic powder filled with polytetrafluoroethylene (PTFE) composites were prepared by casting and vacuum hot-pressing methods. The surface hydrophobicity of the particles and the interfacial compatibility of the composites were improved by using Z6124 coupling agent. Compared with the pure PTFE, the 55 wt% Z6124 modified MGSA particles filled PTFE composite board showed a high dielectric constant of 3.5 and lower dielectric loss of 9 × 10 −4 @10 GHz as well as a thermal conductivity of 0.734 W/mK, which is three times order than that PTFE @0.2 W/mK. Based on the above experiments, simulations of their dielectric properties and thermal conductivity were carried out with COMSOL Multiphysics. The results show that the 65 wt% MGSA particles construct the best thermal conductivity path filled PTFE composite board, which is consistent with the experimental results. All these properties indicate that Z6124 modified MGSA particle filled PTFE composites are potential materials for microwave substrate applications.