Synthesis and properties of chlorinated polyimides

A series of diamines with various chlorine content was synthesized. Using t hese novel diamines, a series of new chlorinated polyimides was prepared by reacting them with 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydri de (6FDA). The purpose was no investigate the effect of the chlorine conten t on the properties of polyimides, such as thermal and optical properties. The in-plane refractive (n(TE)) indices of polymer films increase with incr easing order of in-plane orientation in these polyimides. The out-of-plane refractive (n(TM)) indices increase with chlorine content