Shandong Helishi Zhongjie Chemical Co., Ltd is specializing in the production of Polyimide monomer for polyimide film, polyimide resin and insulation materials. Our main products are Pyromellitic Dianhydride(PMDA) and 4,4'-Diaminodiphenyl Ether(ODA). The annual output of PMDA is 1500mt and ODA is 1000mt. Both of the two product