Preparation and characterization of polyimide/ladder like polysiloxane hybrid films

Novel polyimide (PI)/ladder like polyphenylsilsesquioxane (PPSQ) hybrid films was prepared. PI was made from poly(amide acid) of 4, 4′’-diaminodiphenylether and pyromellitic dianhydride. PPSQ was prepared from phenyltrimethoxysilane through sol–gel process. The chemical structure of PPSQ was characterized by Fourier transform infrared and nuclear magnetic resonance. The coefficients of thermal expansion for the hybrid films decrease with the increasing content of PPSQ. The thermal and mechanical properties of the hybrid films were essentially similar to the neat PI.