| 초록 |
Numerous studies have been devoted to the syntheses, processing of biodegradable thermoplastics such as poly(caprolactone), poly(L-lactide) and poly(3-hydroxybutyrate). More recently, the synthesis of biodegradable polymers in superciritical CO2(sc CO2) has attracted more attention. Supercritical CO2 is an adequate reaction medium because of its low toxicity, low cost and nonflammability. In coordination-insertion polymerization of L-lactide promoted by Al, Zn and Sn compounds as catalyst in bulk, in solution and in sc CO2, the structure of the active species, the reactivity of the initiators including a hydroxyl group bearing reagents and their contribution to propagation and side reactions (e.g. intra- and intermolecular transesterifications) are known. However, nothing is known about the mechanism and kinetics of homogeneous ring-opening polymerization of L-lactide promoted by tin octoate in supercritical chlorodifluoromethane. This paper reports preliminary results about the ring-opening polymerization of L-lactide initiated by 1-dodecanol/tin octoate in supercritical chlorodifluoromethane. |
