The interactions between organic and inorganic components in pregel solution for polyacrylamide (PAAm)/clay nanocomposite hydrogels (NC gels) and in prepared NC gels are investigated. Besides, a kind of self-crosslinked PAAm gels with excellent mechanical properties is fabricated in the absence of any cross-linking agents, the hydrogen bonding interactions among PAAm chains are acted as the cross-linking force. It is revealed that the binding interactions of PAAm and clay in NC gels are owing to the noncovalent interactions between amide groups on PAAm chains and clay platelets, which afford the cross-linking force for NC gels network formation. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 263-266, 2011