A Novel Route to Aryl Diether Dianhydrides

Abstract

Aryl diether diphthalic anhydrides have been prepared by the reaction of a diphenol with 4-fluorophthalic anhydride and KF in the presence of a polar, aprotic solvent. The KF acts as an HF acceptor and obviates the need for preparing the disodium salt of the diphenol in a separate step. The diether anhydrides of biphenol, hydroquinone, resorcinol, dihydroxybenzophenone and bisphenol-A have been prepared in this fashion. Two of these dianhydrides have been used to prepare polyetherimides via their reaction with selected diamines. These materials form creasable films having good thermal stability.