The study presents the synthesis of an acrylamide polymeric hydrogel in aqueous solution by copolymerization concomitant with a crosslinking process using a bifunctional co-monomer with a redox initiation system--potassium peroxo-disulphate/ascorbic acid. The swelling kinetics as well the characterization of structure through optical microscopy was performed. The synthesized polymeric gel shows temperature sensitivity, maintaining low temperatures for a prolonged period of time. Thus, the material is assessed as an inner material in thermo sensitive packs to be applied in pain therapy.