| Summary: | Bisphenol A (BPA) is the principal component of many polymers such polycarbonate (PC) and epoxy resins. These polymers are commonly used to make baby bottle, drinking water bottle, CDs, food containers, dental sealant, and so on. BPA can migrate from PC to foods and beverages. In order to establish the relationship between the migrant contaminant and its polymer, and explain the release mechanism of the BPA, the impact of different factors on PC aging was studied by measuring molecular masses using size exclusion chromatography (SEC). It has been found that the molecular weights of PC samples change as a function of treatment conditions. In general, the trend was to shift the Mn toward a lower average molecular weight with increasing treatment temperature, pH and treatment duration. The same PCs were explored by Thermogravimetric analysis (TGA), and its degradation kinetic was studied. The PC decomposition follows the Arrhenius law, which allows the determination of the activation energy (Ea) from thermal degradation curves with Friedman isoconversional method. The results show clearly that the activations energies which indicate the threshold of degradations reactions decrease with increasing temperature and pH.
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