Preparation and Characterization of Polylactic Acid by Ring Opening Polymerization Using Unconventional Heating System
Keywords:polylactic acid, microwave techniques, biodegradable polymers, green chemistry
Polylactic acid (PLA) has been synthesized via ring opening polymerization (ROP) for the Lactide cyclic dimmer under microwave irradiation with a constant power of 300W using ZnO catalyst. The structural formula of PLA was established using spectroscopic techniques FTIR, 1HNMR, and 13CNMR. The thermal properties were investigated using DSC and TGA techniques. The DSC thermogram exhibited two endothermic transitions at (115-132) C° which related to the melting of the polymer, while the TGA thermogram showed one main decomposition step at 265°C. The viscosity average molecular weight  of the obtained polymer was (7.8×103 gm/mol). The SEM morphology study exhibited homogenous and dense surface with no separate entities
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