The Synthesis And Characterization Of Polyimide Film

Polymide(PI) has excellent performance in the field of high technologies. However, it is difficult for most polymide to dissolve, fuse and process. Its application has been restricted to some extent. Therefore, more attention is paid to develop high processed polyimide.Three polyimide films were prepared by reacting pyromellitic anhydride (PMDA) respectively with three diamine, 1,4-bis(4-nitrophenoxy) benzene(TPE-Q), l,3-bis(4-nitrophenoxy) benzene(TPE-R), and 2,2'-dimethyl-4,4'-diaminobiphenyl(m-TB), via a two-step polymerization procedure. During the synthesis, the technological parameters of synthesis were optimized and the reaction time is about 3 hours. FT-IR was employed to characterize the structures of polyamic acid and polyimide. In different solvents, polyimides almost insoluble except concentrate sulfuric acid. It is pruved by TGA that it has high thermal stability. Their Tg were determined by DSC.