Homo- and Copolymerization of ε-Caprolactone and 2,2-Dimethyltrimethylene Carbonate by Rare Earth Initiators

• 来源期刊: 中国化学(英文版)
• 年，卷（期）: 2002,（11）
• 页码范围: 1369-1374
• 页数: 6页
• 语种: 英文

摘要

Rare earth tris(2,6-di-tert-butyl-4-methylphenolate) [ Ln(OAr)3, Ln=La, Nd, Dy, Y] alone has been developed to initiate polymerization of ε-caprolactone (CL) and random copolymerization of CL with 2,2- dimethyltrimethylene carbonate(DTC). The structures of polymers were analyzed by GPC, IR and NMR methods. Their crystal and thermal properties were discussed in terms of DSC. The initiating efficiencies were mainly affected by the size of rare earth metal in the se-quence of La(OAr)3 ＞ Nd(OAr)3 ～ Y(OAr)3 ＞ Dy(OAr)3. La(OAr)3 exhibited rather high activity to prepare PCL with a molecular weight of 2.15 × 105 and Mw/Mn of 2.27. The composition of random copolymer can be quantitatively controlled either by reaction time or by feed ratio of monomer.