Polyelectrolyte catalysis

The polyelectrolyte catalysis of chemical reactions involving ionic species has been the subject of extensive investigations since the pioneering studies of Morawetz et al. [12] and Ise et al. [13-17]. The catalytic effect or the ability of poly-electrolytes to enhance or retard reaction rates is mainly due to concentration or exclusion of either or both of the ionic reactants by the polyions added to the reaction systems. For example, the chemical reaction between ionic species carrying the same charge is enhanced in the presence of polyions carrying the opposite charge. This enhancement can be attributed to an increase in the local concentration... 

In a continuation of their work on polyelectrolyte catalysis in ionic reactions, Ise and co-workers studied the effect of some cationic polyelectrolytes 20 in the hydrolysis of dinitrophenylphosphate dianion 21 (30). The dianion undergoes spontaneous decomposition [cf. Eq. (3—3)] (31, 32). The polycations employed are... 

The first part of the book is devoted to the basic properties of polyelectrolytes in general, namely to the factors influencing the chain conformation of charged polymers in solution and to their counterion selectivity. It also contains methods of synthesis and new concepts of charge stabilized polymer colloids and of polyelectrolyte catalysis. 

Finally comments are necessary on a general feature of the polyelectrolyte catalysis. As stated in the introductory part, high molecular weight compounds are more efficient in accelerating chemical reactions under appropriate conditions. It should be noted that this statement is not always justified. For example, polyvinylpyridine is less efficient than 4-picoline in enhancing the solvolysis of dinitrophenyl acetate [62], whereas this polymer is extremely efficient compared to 4-picoline for the solvolysis of 5-nitro-4-acetoxysalicylic acid. Imidazole was 50 times more efficient than polyvinylimidazole in the formation of N-acyl compounds of p-nitrophenyl acetate in dimethylformamide [63]. In the hydrolyses of butylacetate and propyl-acetate, dodecyl benzenesulfonic acid was 6 and 3 times more eflScient than polystyrene sulfonate, respectively [64]. 

Other studies have dealt with the aquation rates of some diacido cobalt(III) tetramine complexes containing asymmetric tetramine ligands, activation parameters for the aquation of frans-[Co(pn)2Cl2] , polyelectrolyte catalysis in the aquation of [Co(ox)3] in binary mixtures... 

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