pH and salt effects on interpolymer complexation via hydrogen bonding in aqueous solutions

The effect of inorganic salts addition on the complex formation of poly(acrylic acid) with various non-ionic polymers such as poly(vinyl pyrrolidone), poly(acrylamide), poly(ethylene oxide), pol(vinyl methyl ether), poly(vinyl alcohol), poly(N-isopropylacrylamide), poly(2-hydroxyethyl vinyl ether), hydroxypropylcellulose and hydroxyethylcellulose has been studied in aqueous solutions. It was found that, depending on the nature of the polymers and pH medium, addition of inorganic salts could increase or decrease the critical pH values of complexation. A new classification of interpolymer complexes based on critical pH values and ionic strength effects is suggested. (C) 2004 Society of Chemical Industry.