Effects of compound compatibilizer and CaTiO3 filler on the properties of polypropylene/polyphenylene ether/glass fiber composites

The present study used polyphenylene ether/Polypropylene/glass fiber (PPO/PP/GF) composites as the matrix material to obtain the dielectric plate material to be used in the dielectric phase shifters for 5G base stations. First, the reinforcement effect of the compound compatibilizers comprising PP-g-MAH and SEBS-g-MAH on the PPO/PP/GF composites was investigated. The experimental results revealed that the compound compatibilizers could dramatically improve the compatibility and performance of the PP/PPO/GF composites through synergistic compatibility. Next, the crystallization effect of CaTiO 3 fillers on the PPO/PP/GF composites was investigated. The DSC analysis revealed that using a small amount of CaTiO 3 promoted the crystallization of PP, while using a large amount of CaTiO 3 inhibited the crystallization effect. At a compatibilizer content of 6 wt% and CaTiO 3 in the range of 10–85 wt%, the CaTiO 3 /PP/PPO/GF composite presented a continuously adjustable dielectric constant (ε r = 2.32–20.9), low dielectric loss (tanδ < 0.0019), and high heat resistance (VST = 169.5–177°C), and could, therefore, be used as a dielectric plate material in the dielectric phase shifters for 5G base stations. Highlights The compound compatibilizers comprising PP-g-MAH and SEBS-g-MAH could dramatically improve the compatibility and performance of the PP/PPO/GF composites through synergistic compatibility. A small amount of CaTiO 3 promoted the crystallization of PP and a large amount of CaTiO3 inhibited the crystallization effect. The CaTiO 3 /PP/PPO/GF composites could serve as ideal dielectric plate materials in the development of dielectric phase shifters for 5G base stations.