SYNTHESIS AND PROPERTIES OF POLYETHER KETONES

Polyether ketones were prepared by the nucleophilic reaction of dihaloaromatic ketones with aromatic bisphenols (hydroquinone, resorcinol and 4,4-dihydroxybenzophenone) using various solvents in the presence of anhydrous K2CO3. Dihaloaromatic ketones (4,4-difluorobenzophenone/4,4-dichlorobenzophenone) were prepared from the reaction of fluorobenzene/chlorobenzene with carbon tetrachloride in the form of AlCl3. The polymers were characterized by different physico-chemical techniques. Thermogravimetric studies showed that all the polymers were stable upto 500-degrees-C with a char yield above 50% at 900-degrees-C in N2 atmosphere. Isothermal degradation at 400-degrees-C under air and N2 atmosphere reveals about 5% weight loss and about 1% weight loss at 75 min respectively. The effect of solvents, reaction temperature and reaction time on molecular weights are discussed. The effect of the annealing time on crystallinity of the polymers is also discussed.