In this work, a new stimuli-responsive composite polymer hydrogel containing partially exfoliated graphite was prepared by frontal polymerization. The materials obtained were characterized by differential scanning calorimetry, RAMAN, scan electron microscopy, transmission electron microscopy, atomic force microscopy, and in terms of swelling behavior. It was found that the maximum temperature reached by the polymerization front and the lower critical solution temperature are affected by the graphite content. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 5375-5381, 2010