POLYELECTROLYTE COMPLEXES .1. SYNTHESIS AND CHARACTERIZATION OF SOME INSOLUBLE POLYANION-POLYCATION COMPLEXES

The synthesis of some water-insoluble synthetic polyelectrolyte comple xes formed between a weak polyanion and a strong polycation was follow ed. Sodium salts of poly(acrylic acid) and of some copolymers of acryl ic acid with itaconic acid or maleic acid were used as anionic polymer s. Cationic polyelectrolytes with quaternary ammonium salt groups in t he main chain were used as strong polycations. The cationic polymers w ere different as concerns both the content of quaternary nitrogen atom s and the degree of branching. The complex formation was followed by t he variation of the conductivity and of the specific viscosity of the reaction medium as well as by the turbidimetric titration versus the u nit molar ratio polyanion/polycation. The deviation of the endpoint fr om stoichiometry was influenced mainly by the structure of the complem entary polymers and by their molecular weights. The greater the struct ural differences, the higher the endpoint deviation from stoichiometry . Only insoluble polyelectrolyte complexes (PEG) were obtained in all the polyanion/polycation systems taken into account. The PECs were sep arated and characterized by elemental and spectral analyses as compare d with the complementary polymers. (C) 1996 John Wiley & Sons, Inc.