We propose a separation technique for a mixture of polymer materials that involves unsteady heat conduction and thermal adhesion. Since the softening temperature is related to the melt or glass transition temperature of these materials, each material has its own adhesion temperature. Further, the adhesion temperature of each material was typically between its glass transition temperature and melt temperature. In the present study, we used these characteristics to separate particular components from a mixture of polymer materials. Five types of virgin polymer pellets were used as test materials in the experiment and two experimental designs were used to investigate the capabilities and characteristics of this separation technique. The first experiment simply consisted of heating and pushing plates. Using this apparatus, the adhesion temperature of each material was determined experimentally and the effect of the surface condition of the test material was investigated. The contaminants on the material surface behaved as a thermally resistant medium, and coloring paint present on the surface significantly affected the adhesion behavior. In order to improve the separation efficiency, we examined another separation system, which consisted of counter-rotating twin rollers. Continuous material separation was achieved using the roller system.