A new approach in compatibilization of the poly(lactic acid)/thermoplastic starch (PLA/TPS) blends

摘要

tIn this study, a new compatibilizer was synthesized to improve the compatibility of the poly(lacticacid)/thermoplastic starch blends. The compatibilizer was based on maleic anhydride grafted poly-ethylene glycol grafted starch (mPEG-g-St), and was characterized using Fourier transform infraredspectroscopy (FTIR), dynamic mechanical thermal analysis (DMTA) and back titration techniques. Theresults indicated successful accomplishment of the designed reactions and formation of a starch coredstructure with many connections to m-PEG chains. To assess the performance of synthesized compati-bilizer, several PLA/TPS blends were prepared using an internal mixer. Consequently, their morphology,dynamic-mechanical behavior, crystallization and mechanical properties were studied. The compatibi-lizer enhanced interfacial adhesion, possibly due to interaction between free end carboxylic acid groupsof compatibilizer and active groups of TPS and PLA phases. In addition, biodegradability of the sampleswas evaluated by various methods consisting of weight loss, FTIR-ATR analysis and morphology. Theresults revealed no considerable effect of compatibilizer on biodegradability of samples.