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This research deals with stabilization of bisphenol-A polycarbonate (PC) against photo-oxidation and thermal-oxidation. The photostabilizers used in this study were poly(p-methylphenyl acrylate)(PMPA) and poly(methyl methacrylate)(PMMA), while the hindered phenol type resin, resole, was used for the antioxidant for PC. Compatibility and intermolecular attraction in systems such as PC/PMPA, PC/PMMA, PC/Resole were investigated with DSC and FT-IR. Photo-oxidation studies were carried out in Q-UV aging accelerator, with ultraviolet range around 280-315nm. Decreases in Vc=o and VG-O-C were used as the criteria for both photo-oxidation and thermo-oxidation of PC. Experimental results revealed that partial compatibility for PC/PMPA and complete compatibility for PC/PMMA and PC/Resole were found, which were evidenced from inner shifts for Tg's and IR bands(Vc=o and VOH). Experimental result also indicated that addition of PMPA and/or PMMA to PC improved the photo-oxidation of PC, and addition of Resole to PC enhanced its thermo-oxidation. While the photostabilization for blends of PC/PMPA/Resole (100/5/5) and PC/PMMA/Resole (100/5/5) were better than blends of PC/PMPA and PC/PMMA.
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