Table 5 presents the results obtained by TGA and DSC thermal analysis of PS before and after exposure to UV radiation. Figure 4 brings the complete results for the DSC analysis. A similarity between the onset decomposition temperatures of the irradiated materials was identified when compared to the as-received PS, guaranteeing thermal stability under the studied conditions. However, the degree of crystallinity increased considerably for the UV-irradiated materials, suggesting the occurrence of rearrangement of the macromolecules that were cleaved in the amorphous region. This corroborates the chromatography and gel content results that were obtained [26, 27].
Table 5. Thermal analysis (TGA / DSC) results obtained for all conditions. Complete results are shown in Figure 4.