of triethylamine and benzoic acid and the protection of nitrogen; a solution casting method and proton exchange are adopted to prepare non-covalent cross-linked sulfonated polyimide film containing imidazolyl which is then processed by methane-sulfonic acid/phosphorus pentoxide solution or phosphoric acid...
cycloolefins and their alkyl derivatives such as cyclohexene and ethylcyclohexene; ethers and esters such as phenyl methyl ether, methyl esters and the fatty acid glycerides; acids such as benzoic acid; and various derivatives of the above compounds containing substituents such as halo, nitro, amino...
The sulphonated phenoxy alkoxyphthalic acid or ester can be reacted with an alkali metal hydroxide or lakoxide or an alkali metal salt of an acid weaker than sulphonic acid, such as acetic or benzoic, to form the corresponding alkali metal sulphonate. The phenoxyalkoxyphthalic acids and esters...