聚醚酯合成中中间过程产物的测定与分析

Determination and Analysis of Intermediate process products In Polyether ester Synthesis

通过PTA法合成PBT-PTMG嵌段聚醚酯,对PTA法合成聚醚酯工艺中的中间过程产物进行了分析与测定。结果表明:酯化反应馏出水中主要包含水、四氢呋喃及少量丁二醇,其中四氢呋喃量(相对馏出水的总量)在酯化反应过程中呈现多-少-多的规律,而丁二醇的量(相对馏出水的总量)总体变化不大;低真空馏出液中主要包含丁二醇、四氢呋喃及少量低聚物,其中低真空初始阶段丁二醇与四氢呋喃摩尔比值为3.15∶1,而低真空中间阶段丁二醇与四氢呋喃摩尔比值为70.07∶1,在低真空阶段抽出的低聚物质量为总馏出液质量的4∶5%,其中PT单元相对较多。

The PBT-PTMG block polyether ester was synthesized by PTA method, and the intermediate process products in the process of synthesis of polyether ester by PTA method were analyzed and determined. The results showed that the esterification reaction of distillate water mainly contained water, tetrahydrofuran and a small amount of butanediol, the amount of tetrahydrofuran ( relative amount of distilled water) showed more-less-more rules in the process of esterification reaction and butanediol ( relative to the total amount of distilled water) changed little over-all;the low vacuum distillate mainly contained butanediol, tetrahydrofuran and a small amount of oligomers, the to-tal amount of butanediol and tetrahydrofuran in the initial stage of low vacuum was 3.15-1, while the molar ratio of butanediol to tetrahydrofuran in the low vacuum intermediate stage was 70. 07- 1;the amount of oligomers extracted in the low vacuum stage was 4. 5% of the total quality of distillate, among which the PT unit was relatively larger.