An epoxydinaphthalene monomer for the synthesis of a poly(aryl ether sulfone) and a poly(aryl ether ketone) with enhanced performance for membrane gas separations.

A novel monomer based on epoxydinaphthalene (EDN), a highly rigid bridged-bicyclic structural unit, was prepared using a high yielding reaction between 2,7-hydroxynaphthalene and the hydrate of 1,8-naphthalene dialdehyde. This monomer was used to make a poly(aryl ether ketone) and poly(aryl ether sulfone), EDN-PAEK and EDN-PAES, via efficient aryl ether bond formation, by reaction with cheaply available co-monomers. Both EDN-PAEK and EDN-PAES proved readily soluble in organic solvents allowing structural characterization and ready fabrication of robust self-standing films. Gas permeability measurements for He, H2, O2, N2, CO2 and CH4 indicated that these polymers provide a good trade-off between high selectivity and modest permeability relative to previously published data for structurally related polyketones or polysulfones.