Linear silicone chains synthesized from dimethyldiethoxysilane are applied to a heat resistive coupling agent in polyamideimide(PAI) composite containing glass. The silicone chains have an effect on improving glass-PAI adhesion. It is also concluded from the results for aged samples that the degradation of silane coupling agent brings about the decrease in dielectric breakdown, and that silicone chains serve as a heat resistive coupling agent.