Sulfonated Poly(ether-Ketone)s Containing Hexafluoroisopropylidene Groups

This is the authors' abstract. We don't add key points for this paper.

An aromatic poly(ether-ketone) derived from 4,4′−(hexafluoroisopropylidene)-diphenol and 4,4′-difluorobenzophenone has been sulfonated by using chlorosulfonic acid in 1,2-dichloroethane, in the presence of trimethylchlorosilane. The resulting modified polymers had different degrees of sulfonation depending on the reaction conditions. The sulfonation reaction with chlorosulfonic acid did not cause much degradation of the initial polymer. The sulfonated polymers are soluble in various polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, pyridine, some in methanol, and could be cast into flexible tough films. The polymers were characterized by elemental analyses, infrared and 1H NMR spectroscopy, gel permeation chromatography, and thermogravimetric analyses. The degree of sulfonation was determined by 1H NMR spectroscopy. Some correlations between the conditions of sulfonation and the properties of resulting polymers have been made.