SYNTHESIS OF SOLUBLE HIGH-MOLECULAR-WEIGHT POLY(ARYL ETHER KETONES) CONTAINING BULKY SUBSTITUENTS

tert-Butyl- and phenyl-substituted poly(aryl ether ketones) were prepared by a nucleophilic substitution reaction from the corresponding substituted hydroquinones and 4,4’-difluorobenzophenone. Reaction temperatures of 170 °C were sufficient to give high molecular weight poly (oxy- (2-tert-butyl-1,4-phenylene)oxy-1,4-phenylenecarbonyl-1,4-phenylene). This polymer was found to be amorphous, Tg = 175 °C, and highly soluble in common organic solvents, such as chloroform, THF, and toluene. The tert-butyl substituent was cleaved with trifluoromethanesulfonic acid in a reversed Friedel-Crafts alkylation reaction to produce PEEK (poly(aryl ether ether ketone)). This reaction proceeded to high conversions in the presence of a tert-butyl group acceptor such as toluene. © 1990, American Chemical Society. All rights reserved.