Chemical modification of polysulfone: anionic synthesis of dipyridyl functionalized polysulfone

A new method for the synthesis of dipyridyl functionalized polysulfone is described. The functionalization process involves the formation of lithiated polysulfone from polysulfone (1) and subsequent reaction with 2,2′-vinylidenedipyridine (2) in tetrahydrofuran at −78°C under argon atmosphere. The dipyridyl functionalized polysulfone (3) was evaluated for the chelation of trace heavy metal ions such as copper and nickel in aqueous medium. The dipyridyl functionalized polysulfone shows better complexing affinity for nickel ions at specific concentrations of test solutions. Quaternization reactions of dipyridyl functionalized polysulfone with dimethyl sulfate in the presence of perchloric acid quantitatively affords the corresponding polymeric pyridinium perchlorate derivative (4).