The paper describes the principles, theoretical calculation procedure, and apparatus used for the realization of the temperature wave technique. The efficiency of the technique for the studies of relaxation transitions in polymers when the thermophysical characteristics are in the complex form has been demonstrated. The temperature dependences of the moduli and arguments of thermophysical characteristics for different frequencies of temperature oscillations have been obtained for polyvinylacetate. The vibrational and configurational components of the heat capacity have been found. The effect of polymer plasticization and also of changes in the chemical composition of molecules on complex thermophysical characteristics has been shown using styrene-butylacrylate as an example.