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.