Adhesion of polyimides to ceramics: Effects of aminopropyltriethoxysilane and temperature and humidity exposure on adhesion

The effects of both y-aminopropyltriethoxysilane (APS) and elevated temperature and humidity (T&H) exposure on the adhesion of pyromellitic dianhydride-oxydianiline polyimide to SiO₂, Al₂O₃, and MgO were studied using XPS, SEM, and peel test. Adhesion and T&H stability of PMDA-ODA on SiO₂ is significantly improved when APS is used at the interface, while no significant improvement is observed for Al₂O₃ or MgO. XPS analysis of the surfaces showed no retention of APS on Al₂O₃ or MgO, while SiO₂ did retain APS, as is expected. The APS retention is affected by surface treatment of the oxide prior to APS application.