SYNTHESIS AND CHARACTERIZATION OF NEW AROMATIC POLY(ETHER KETONE)S

A general method for the preparation of aromatic poly(ether ketone)s c ontaining amide, amide-imide, cyano, oxadiazole, and pyridazine moieti es has been developed. Polymerization is based on a ketone-activated h alide displacement from amide-, amide-imide-, cyano-, oxadiazole-, or pyridazine-containing bis(4-fluorobenzoyl) moieties by bisphenoxides i n a polar aprotic solvent. The bis(4-fluorobenzoyl) moieties were prep ared by reaction of 4-fluorobenzoyl chloride with diphenoxy monomers c ontaining amide, amide-imide, cyano, oxadiazole, or pyridazine groups under modified Friedel-Crafts conditions in methylene chloride. All of the polyether ketones prepared were amorphous and exhibited T(g)s ran ging from 134 to 218 degrees C. In addition, films of the aromatic pol yether ketones displayed good thermal stability and flexibility. The d ielectric constants of the films were characterized as a function of r elative humidity (RH). (C) 1995 John Wiley and Sons, Inc.