Low-Loss Sr2Ti9O20-Filled Butyl Rubber Composites for Miniaturized Flexible Microwave Substrate Applications

Low-loss Sr2Ti9O20 (STO)/butyl rubber (BR) composites have been prepared by mixing and hot pressing. X-ray diffraction and energy-dispersive spectroscopy are employed to investigate the phases contained in the STO filler, and the microstructural characteristics of the composites are discovered using scanning electron microscopy. The STO/BR composites demonstrate a high relative permittivity of 10.98 and a low loss of 0.003 at 10 GHz, corresponding to an optimum filler volume fraction of 45%. In addition, a low coefficient of thermal expansion of 50.72 ppm degrees C-1 and a high thermal conductivity of 0.9603 W m(-1) K-1 have been found for the optimum composition, with an acceptable moisture absorption of 0.071%. The obtained composites can be employed for miniaturized, flexible radio-frequency substrate applications.

Automated summary

Low-loss Sr2Ti9O20 (STO)/butyl rubber (BR) composites with high relative permittivity and low coefficient of thermal expansion have been prepared for flexible radio-frequency substrate applications.