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• 作者：Weizhong Yuan ; Jinying Yuan ; Fengbo Zhang ; Xuming Xie
• 刊名：Biomacromolecules
• 出版年：2007
• 出版时间：April 2007
• 年：2007
• 卷：8
• 期：4
• 页码：1101 - 1108
• 全文大小：1066K
• 年卷期：v.8,no.4(April 2007)
• ISSN：1526-4602

文摘

Well-defined ethyl cellulose-graft-poly(-caprolactone) (EC-g-PCL) graft copolymers were successfully synthesizedvia ring-opening polymerization (ROP) of -caprolactone (CL) with an ethyl cellulose (EC) initiator and a tin2-ethylhexanoate (Sn(Oct)₂) catalyst in xylene at 120 C. Then, novel ethyl cellulose-graft-poly(-caprolactone)-block-poly(L-lactide) (EC-g-PCL-b-PLLA) graft-block copolymers were prepared by ROP of l-lactide (L-LA)with a hydroxyl-terminated EC-g-PCL macroinitiator and Sn(Oct)₂ catalyst in bulk at 120 C. Various graft andblock lengths of EC-g-PCL and EC-g-PCL-b-PLLA copolymers were obtained by adjusting the molar ratios ofCL monomer to EC and the L-LA monomer to CL. The thermal properties and crystalline morphologies of EC-g-PCL and EC-g-PCL-b-PLLA copolymers were different from those of linear PCL. The in vitro degradationrate of EC-g-PCL-b-PLLA was faster than those of linear PCL and EC-g-PCL due to the presence of PLLAblocks.