1,1,1-三羟基丙烷为核的三臂星型聚乙二醇合成及表征

SYNTHESIS AND CHARACTERIZATION OF THREE-ARM STAR-SHAPED POLYETHYLENE GLYCOLS WITH 1,1,1-TRIHYDROXMETHYLPROPANE AS CORES

以1,1,1-三羟甲基丙烷与过量癸二酸二乙酸酐反应,制得了端羧基的三官能度小分子核三癸二酸三羟甲基丙烷酯(TMP-SK3).在辛酸亚锡催化下,以二苯醚为共沸脱水剂,将三官能度小分子TMP-SK3作为偶联剂,进一步与不同分子量的端羟基聚乙二醇(PEG)和聚乙二醇单甲醚(PEGm)缩合,减压下共沸脱水,制备了以TMP-SK3为核,PEG或PEGm为臂的三臂星形大分子.通过1H-NMR,DSC,GPC,XRD等手段对所得聚合物进行了表征.DSC测试结果表明,与线型聚乙二醇相比,三臂星型聚乙二醇由于TMP-SK3核的存在,不仅影响聚乙二醇的结晶速度,同时也影响结晶的完善程度,导致其结晶温度和结晶熔融温度发生变化.

A small molecule core （TMP-SK3）with three terminal carboxyl groups was synthesized successfully by the reaction of 1,1,1-trihydroxymethylpropane with the excessive sebacic acid diacetic anhydride. Then, the core molecule was used as a coupling agent to condensate with polyethylene glycols （PEG）of different molecular weight or polyethylene glycol monomethyl ether （PEGm）in the presence of stannous octoate as catalyst and diphenyl ether as azeotropic agent to remove water. Thus, the three-arm star-shaped polyethylene glycol was obtained successfully, and was characterized by ^1H-NMR, DSC, GPC and XRD, etc. DSC measurements indicate that the crystallizing temperature and the melting temperature of the three-arm star-shaped polyethylene glycol were different from those of the corresponding linear PEG because the existing of TMP-SK3 altered its crystallizing velocity and the perfect degree of crystals.