The modification of polysulfone by metalation

Chemical modification of aromatic polysulfones by sulfonation and chloromethylation provides polymers with functional groups which make them more versatile as membrane materials. Lithiation has been employed in the modification of polystyrene, poly(2,6-dimethyl-1,4-phenylene)ether, polyvinylthiophene, and styrene-sulfur dioxide copolymers, but has not been investigated as a method of modification of polysulfone. Polysulfone possesses aryl sulfone groups in the structure which strongly activate towards ortho-lithiation as previous studies on simple diphenyl-sulfones have shown, making this polymer a particularly suitable substrate. A recent paper concerning the preparation of carboxyl containing polysulfone by room temperature lithiation prompts us to disclose our own related work on the subject. Our studies of changes in membrane characteristics brought about by various types of functional groups led to the development of this versatile modification approach in which a diverse range of substituted polymers are attainable. In this letter, the position and degree of lithiation was examined by 1H-NMR spectral analysis of two simple derivatives.Peer reviewed: NoNRC publication: Ye