A series of novel dual functional nanocomposite hydrogels were prepared from N-isopropylacrylamide (NIPAAm), acrylic acid (AA) that is neutralized 50 mol % by sodium hydroxide (SA50), and montmorillonite (MMT). MMT was intercalated with three different contents of intercalation agent of (3-acrylamidopropyl) trimethyl ammonium chloride (TMAACI). Investigation of the effect of intercalated MMT with three contents of intercalation agent (TMAACI) in the present nanocomposite hydrogels on the swelling and drug release behaviors is the main purpose in this study. The microstructure was identified by X-ray diffraction (XRD). Results showed that the swelling ratio for the present nanocomposite hydrogels decreased with an increase in the content of the intercalation agent. The gel strength of the present gels did not change obviously with an increase in the content of intercalation agent. XRD results indicated that exfoliation of MMT was achieved in the dry and swollen gel state. Finally, the drug release behaviors for these gels were accessed also. (C) 2004 Wiley Periodicals, Inc.