反应详情

The procedure of Example II is repeated except that 20 grams of L-(-)-lactide, 30 grams of epsilon caprolactone and 0.0105 grams of pure stannous octoate are placed in a glass flask, blanketed with nitrogen, and heated for 45 hours at 140° to 142° C. The copolymer is tough and elastic and has good tensile strength and elongation properties. The copolymer has a GPC molecular weight of Mw =323,000 and Mn =180,000. DSC of the copolymer reveals a moderate amount of crystallinity with a melting point endo-therm of 42° C. and a glass transition temperature of -16° C. Physical properties of the polymer are shown in Table 1.

1. customare placed in a glass flask
2. temperatureheated for 45 hours at 140° to 142° C
3. customwith a melting point endo-therm of 42° C.