Effect of intercalated hydrotalcite on swelling and mechanical behavior for poly(acrylic acid-co-N-isopropylacrylamide)/hydrotalcite nanocomposite hydrogels

A series of nanocomposite hydrogels were prepared from acrylic acid (AA), N-isopropylacrylamide (NIPAAm), and intercalated hydrotalcite (IHT) by photopolymerization. The influence of the intercalating content of 2-acrylamido-2-methyl propane sulfonic acid (AMPS) in HT on the swelling and mechanical properties for poly(AA-co-NIPAAm)/IHT nanocomposite hydrogels was investigated. The results showed that the higher the content of the AMPS-HT was, the higher the swelling ratio of the gels and the higher the content of the intercalating agent was, the lower swelling ratio. It was also demonstrated that the swelling ratio of the gel was not affected by the counterion in HT. The gel strength and crosslinking density were not enhanced by adding AMPS-HT into the gel composition, but the maximum effective crosslink density and shear modulus of the nanocomposite hydrogels were increased with an increase of the content of the intercalating agent in HT. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1572–1580, 2005