Polymeric foams from recycled thermoplastic poly(ethylene terephthalate)

With the increase use of plastics, there is currently a concern with the waste of materials, resulting in a series of challenges and opportunities for the waste management sector. In the present work, poly(ethylene terephthalate) (PET) foam was produced from recycled PET (RPET) from used water bottles. The recycled material was manually prepared and foamed in batches with the assistance of nitrogen gas as the physical blowing agent. RPET was characterized using Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). The influence of the pressure on the foam formation was studied and the results obtained showed that this variable influences the final product characteristics. To evaluate the behavior of the foams, their morphology, response to deformation when subject to compression and their thermal conductivities were studied. The morphology analysis showed that operating at higher-pressure results in bigger pore size but also in an increased pore size heterogeneous distribution, and foams that exhibit a higher thermal conductivity.