Biodegradable starch-based plastics are formed by combining corn starch with biodegradable poly(butylene adipate-co-terephthalate) (PBAT). Starch reduces the production cost and improves the biodegradability. However, starch reduces the ductility and toughness of biodegradable plastics, limiting their application. In this study the low molecular weight poly(ethylene ether carbonate) (LPEEC) is synthesized by the ring-opening polymerization of ethylene carbonate produced from the greenhouse gas CO2. The extrusion combines starch-based plastic with LPEEC and provides plastics with increased tensile strength (by 3- to 4-fold) and elongation at break (by 4- to 5-fold), compared to that of plastics without LPEEC. The plastics with best mechanical properties are obtained using an LPEEC with the average molecular weights, molecular units of ethylene carbonate (Ec) and ethylene oxide (Eo) linkages of 3117 g/mol, 14, and 43, respectively. This is the first evidence of improving the properties of the starch-based polyester using LPEEC, which is suitable for biodegradable plastic.
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