A study of the ring-opening polymerization (ROP) of L-lactide by Ph2SnX2 precursors (X = NMe2, OPri):: the notable influence of initiator group

被引：45

作者：

Chisholm, MH ^{[1
]}

Delbridge, EE ^{[1
]}

机构：

[1] Ohio State Univ, Dept Chem, Columbus, OH 43210 USA

来源：

NEW JOURNAL OF CHEMISTRY | 2003年 / 27卷 / 08期

关键词：

D O I：

10.1039/b300351e

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Studies of the ring-opening polymerization (ROP) of L-lactide by Ph2SnX2 reveal that X (X = NMe2 or OPri) influences not only the rate of polymerization but also the nature of the polymer formed. Gel permeation chromatography (GPC), mass spectral analysis and H-1 NMR spectroscopy of the polymers from these reactions revealed that for X = NMe2, a bimodal molecular weight distribution of polylactide (PLA) is obtained. This is indicative of both cycles and long chains (24 kDa) being formed by both intra- and interchain transesterification. This extensive transesterification results in regeneration of the Ph2Sn[OCHMeC(O)NMe2](2) species as the resting state of the tin(IV) species. Conversely, for X = OPri only a unimodal molecular weight distribution is observed in addition to Ph2Sn[OCHMeC(O)OPri](2), which is indicative of only interchain transesterification. Similar observations were seen in studies of ROP of L-lactide by Ph3SnX precursors.

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页码：1177 / 1183

页数：7

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