This investigation studied the recovery of styrene materials with mech. recycling of different natural domestic waste. The aim of this work was to evaluate the possibility of obtaining a material capable of competing, in some respects, with the virgin material. The two main problems of the recycling and recovery process were also addressed. These include the presence of impurities from other plastic materials, such as polyvinyl chloride (PVC) or polypropylene (PP), and the degradation of the recovered materials due to previous processing or the activities of external agents such as sunlight. In both cases, it was found that the recovered material exhibits a decrease in its mech. properties and it is also difficult to recover. The use of the instrumental-anal. techniques, such as differential scanning calorimetry (DSC), is essential for predicting the quality of the material recovered from the residue.