POLY(SULFOPROPYLBETAINES) .6. CATALYSIS OF INTER-IONIC REACTIONS IN AQUEOUS-SOLUTION BY POLYZWITTERIONS

The 'catalytic' effects of polyzwitterions on aqueous inter-ionic reac tions were studied through the analysis of the influence of a represen tative zwitterionic macromolecule, poly(diethyl-(2-methacryloyloxyetho xy-2-ethyl)-1 -(3-sulfopropyl) ammonium betaine], on two model inter-a nionic and inter-cationic reactions, i.e. oxidation of ferrocyanide by persulfate and aquation of a bromopentaalnminecobalt complex. The ani onic system is clearly accelerated, but considerably less than with a cationic polyelectrolyte of similar structure, riethyl-(2-methacryloyl oxyethoxy-2-ethyl)-ammonium methylsulfonate. A small model zwitterion, (C2H5)(3)-N+-(CH2)(3)-SO3-, has no effect. The inter-cationic reactio n is not accelerated by the polyzwitterion. Copyright (C) 1996 Elsevie r Science Ltd.