The dielectric relaxation mechanisms in a poly(p-hydroxystyrene) derivative have been studied by Thermally Stimulated Depolarization Currents (TSDC) in the temperature range between - 160 and 130 degrees C. A broad relaxation was observed at low temperatures, from -160 up to 0 degrees C, which obeyed to the zero entropy approximation. In contrast, the glass transition relaxation showed the usual behavior, a strong departure to the zero entropy prediction. Both relaxations have been studied in detail by the technique of thermal sampling. The thermal behavior of this poly(p-hydroxystyrene) derivative was also studied by Differential Scanning Calorimetry in the temperature range between 20 and 200 degrees C.