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For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 ℃. The copolymer compositions were determined by ~1H NMR spectroscopy. The monomer reactivity ratios were evaluated by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D,L-3- methylglycolide and glycolide or D,L-lactide are rmg = 0.73, rga = 1.47, rmg = 1.71, r1a.= 0.92, respectively.
For monomer reactivity ratios study, the copolymerization of D, L-3-methylglycolide (MG) with glycolide (GA) or D, L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 ° C. The copolymer compositions were determined by ~ 1H NMR spectroscopy. The monomer reactivity ratios were expressed by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D, L-3-methylglycolide and glycolide or D, L-lactide are rmg = 0.73, rga = 1.47, rmg = 1.71, r1a. = 0.92, respectively.