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应用液-固硅胶柱层析法,以石油醚-乙酸乙酯-异丙醇不同配比为逐段梯度淋洗剂,将环氧丙烷-四氢呋喃共聚醚醇按官能度进行分离。各级份的数均分子量(M_n)和羟基当量(M_E)分别用气相渗透压法(VPO)和红外光谱法测定。根据各级份的官能度(f_n=M_n/M_E),通过计算可得到共聚醚醇的官能度分布,即零、一、二和三官能度组份的相对含量。计算的各种平均官能度与其它方法的测定值相接近。评价了柱层析法的测定准确性和重复性,证明本文提出的方法对测定共聚醚醇官能度分布是有效、可靠的。
The liquid - solid silica gel column chromatography, petroleum ether - ethyl acetate - isopropanol different ratio of gradient eluent for the paragraph, the propylene oxide - tetrahydrofuran copolyether alcohol by functional separation. The number average molecular weight (M_n) and hydroxyl equivalent (M_E) of each fraction were determined by gas phase osmotic pressure (VPO) and infrared spectroscopy respectively. Based on the functionality of each fraction (f_n = M_n / M_E), the functional distribution of the copolyether alcohols, ie, the relative amounts of zero, one, two and three functional components can be calculated. The calculated average functionality is close to that of other methods. The determination accuracy and repeatability of the column chromatography were evaluated. The results show that the proposed method is effective and reliable for the determination of the copolyether alcohol functional distribution.