Aromatic poly(ether imide)s bearing isopropylidene or hexafluoroisopropylidene links in the main chain

Two bis(ether anhydride) monomers, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (4) and 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride (4-F), were synthesized from readily available compounds in three steps in high yields. Two series of poly(ether imide)s 7(a-g) and 7(a-g)-F based on dianhydrides 4 and 4-F, respectively, were synthesized by a conventional two-step procedure that included a ring-opening polyaddition to give polyamic acid)s, followed by cyclodehydration to polyimides. The intermediate poly(ether amic acid)s and the poly(ether imide)s had inherent viscosities in the range of 0.29-1.09 dL g(-1) and 0.21-0.98 dL g(-1), respectively. Except for the poly(ether imide)s derived from benzidine, the others afforded flexible and tough films. Most of the obtained poly(ether imide)s are organic-soluble. The glass transition temperatures (T-g) of these polymers ranged from 204 to 259 degrees C. Degradation temperatures for 10% weight loss all occurred above 505 degrees C in nitrogen and above 501 degrees C in air. Fluorine-containing polyether imide)s showed higher solubility, T(g)s and degradation temperatures in nitrogen, as compared to their respective nonfluorine-containing counterparts.