酯交换聚合法合成聚碳酸酯二元醇的研究

Study on synthesis of polycarbonate diol by transesterification polymerization method

选用碳酸二乙酯(DEC)与1,4-丁二醇(BDO)为反应物,钛酸四丁酯为催化剂,通过酯交换聚合反应合成了一系列数均分子量在1 300～2 800之间的聚碳酸酯二元醇(PCDL)。用傅里叶变换红外光谱和核磁共振波谱(NMR)表征了产物的化学结构,用羟值测定和NMR两种方法测试了产物的数均分子量,用气相色谱/质谱联用法分析了常压馏分的组成。研究表明,当反应物DEC/BDO摩尔比处在1.00～1.07范围内,PCDL的分子量随着它们的摩尔比增加而升高,常压馏分组成变化不大。

A series of polycarbonate diols (PCDL) with number average molecular weights of 1 300~2 800 were synthesized by transesterification polymerization using diethyl carbonate (DEC), 1,4-butanediol (BDO) as reactants and tetrabutyl titanate as catalyst. The chemical structure of the product was characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy (NMR). The number average molecular weight of the product was measured by hydroxyl value determining method and NMR. The composition of the fraction obtained under atmospheric pressure was analyzed by gas chromatography/mass spectrometry. The results showed that, when the molar ratio of DEC/BDO was within the range of 1.00~1.07, the molecular weight of PCDL was raised with the increase of their molar ratio, and the composition of the fraction was not significantly changed.