Effects of compatibilizers on the mechanical, morphological, and thermal properties of poly(propylene carbonate)/poly(methyl methacrylate) blends

The effects of compatibilizers on the mechanical, morphological, thermal, and rheological properties of poly(propylene carbonate) (PPC)/poly(methyl methacrylate) (PMMA) (70/30) blends were investigated. Three different compatibilizers were used in this study: poly(styrene-g-acrylonitrile)-maleic anhydride (SAN-g-MAH), poly(ethylene-coglycidyl methacrylate) (EGMA) and maleic anhydride (MAH). Tensile strength of the PPC/PMMA (70/30) blend increased with the addition of SAN-g-MAH up to 5 parts per hundred resin by weight (phr). In the morphological studies of the PPC/PMMA (70/30) blend with the SAN-g-MAH 5 phr, the droplet size of the PMMA decreased most significantly (from 3.4 to 0.9 μm) compared to those of the blends with the EGMA and MAH. Glass transition temperature (T_g ) of the PPC-rich phase in the PPC/PMMA (70/30) blends shifted to the higher temperature when the SAN-g-MAH was added up to 5 phr. Thermal stability of the blends was improved by the addition of SAN-g-MAH (5 phr). Complex viscosity of the PPC/PMMA (70/30) blends were increased when the SAN-g-MAH was added up to 5 phr. From the above results in mechanical, morphological, thermal and rheological studies of the PPC/PMMA (70/30) blends, it is suggested that the most effective compatibilizer is the SAN-g-MAH and its optimum content in the blend is 5 phr in this study.