Poly(Ether sulfone)s made from 4,4′-dihydroxystilbene and 4,4′-difluorodiphenylsulfone: Synthesis,crosslinking, and epoxidation with hydrogen peroxide

High molecular weight polymers from trans-4,4′-dihydroxystilbene, bisphenols, and 4,4′-difluorodiphenylsulfone were synthesized by a nucleophilic displacement reaction using DMAc as solvent in the presence of potassium carbonate. Characterization and crosslinking studies of these polymers were carried out by DSC, TGA, TMA, x-ray diffraction, and solution and solid NMR. It was found that all polymers can be crosslinked to some extent on heating to 350°C. We also studied the epoxidation of these polymers with hydrogen peroxide in the presence of methyltrioctylammonium tetrakis (diperoxotungsto) phosphate (3—) as the catalyst in a biphasic system. The epoxidized polymers are thermally cross-linkable. Very efficient crosslinking was obtained by heating the epoxidized polymers at 350°C under nitrogen. © 1995 John Wiley & Sons, Inc.