SODIUM SULFONATE-FUNCTIONALIZED POLY(ETHER ETHER KETONE)S

A new monomer, sodium 5,5'-carbonylbis(2-fluorobenzenesulfonate) (1), was synthesized by sulfonation of 4,4'-difluorobenzophenone (2) with f uming sulfuric acid. Poly(ether ether ketone)s containing sodium sulfo nate groups were synthesized directly via aromatic nucleophilic substi tution from the sodium sulfonate-functionalized monomer 1 and Bispheno l A (3) in the presence of potassium carbonate in dimethyl sulfoxide. The polycondensation proceeds without any side reactions. The differen tial scanning calorimetry measurement indicated that the polymers are amorphous and the glass transition temperatures increase with the cont ent of sodium sulfonate groups in the polymer chain. The degree of sub stitution with sodium sulfonate groups has strong influence on their t hermal stability and solubility.