Abstract:
Polycarbonate (PC), one of the engineering thermoplastic, has been attractive to use in various applications owing to its excellent impact resistance and transparency. However, the poor scratch resistance of PC could limit some applications. In this research, the scratch resistance of PC is aimed to be improved by blending PC with poly(methyl methacrylate) (PMMA). PMMA is well known for high scratch resistance but also has some limitations like low impact strength. Then, the blend of PC and PMMA can cause the synergistic properties of PC and PMMA. PC/PMMA alloys generally are immiscible blends which produce phase separation of these two components and result in poor mechanical properties especially the impact strength. In order to improve the compatibility between PC and PMMA, the compatibilizers, poly(ethylene-co-methacrylic acid) (EMAA), ethylene methyl acrylate copolymer (EMA) and ethylene/methyl acrylate/glycidyl methacrylate terpolymer (EMG), were selected to improve the compatibility of alloys. Most compatibilizers improve the impact strength of the alloys but the drawback is the opaque of alloy resin. To maintain the transparency of PC and PMMA, the transesterification catalysts samarium acetylacetonate hydrate (SMACA) and Tin(Il)chloride dihydrate(SnCl₂.2H₂O), were chosen to generate the graft copolymer of PC and PMMA for compatibilization. According to the study, PC80/PMMA20/EMA5 and PC80/PMMA20/EMGl alloys exhibited the outstanding properties in impact strength than can comparable to neat PC. Therefore. they were selected to compare with commercially available benchmarks.
