We earlier reported the role of hydrophobic and hydrogen bondinginteractions on the transition temperatures of thermoreversible copolymergels. We show here that the chemical structure of the hydrophobe and its concentration determine the transition temperatures [lower critical solution temperature (LCST)] and the heat of transition of new hydrophobically modified poly (N-isopropyl acrylamide)[PNIPAm] copolymergels. The gels, prepared by ...