Polyaromatic ether‐ketones from o,o′‐disubstituted diphenyl ethers

Polyaromatic ether‐ketone resins with potentially open structures which are possibly useful as membranes were prepared from diphenyl ethers with alkyl substitutions in the ortho positions and isophthaloyl or terephthaloyl chloride by Friedel–Craft‐type polymerization. These polymers are soluble in such solvents as DMF, DMA, and CHCl 3 , and can be cast into colorless transparent films.