聚己二酸二元醇酯合成研究与表征

Synthesis and Characteristic of the Adipic Acid and Binary Alcohol Polyester

以己二酸、1,2-丙二醇、1,3-丁二醇和1,4-丁二醇为原料,钛酸四正丁酯为催化剂,2-乙基己醇为封端剂,经酯化、缩聚合成己二酸系列聚酯产品。考察了反应时间、催化剂、原料配比和封端剂用量等因素对聚己二酸类酯合成的影响。采用旋转黏度计、红外光谱仪(IR)、核磁共振仪(1H-NMR,13CNMR)、凝胶渗透色谱(GPC)和热重分析仪(TG-DSC)分别对产物的黏度、结构、分子量和热稳定性进行了系统的表征,实验表明:合适的反应条件为聚己二酸1,2-丙二醇酯原料二元醇/二元酸的摩尔比为1.14:1、催化剂为原料总量的0.03%、反应温度为200～220℃、反应时间为6h,此时产物分子量为1.90×103,分布指数为1.4、聚合度n为10的聚酯。聚己二酸1,2-丙二醇酯、聚己二酸1,4-丁二醇酯和聚己二酸1,3-丁二醇酯的分解温度为334℃、349℃和358℃,产物具有较高的热稳定性。

Using tetra-n-butyl titanate as catalyst, 2-ethyl-hexanol as chain-ending reagent and adipic acid, 1,2-propylene glycol, 1,3-butanediol and 1,4-butanediol, respectively, as raw material, series polyester products of adipic acid were prepared via polyesterification reaction. The influences of the reaction conditions, such as the reaction time, the catalyst dosage, the stuff ratio and the amount of used chain-ending reagent were investigated. The rotational viscosimeter, infrared spectrum （IR）, nuclear magnetic resonance apparatus （^1H-NMR, ^13CNMR）, gel permeation chromatograph （GPC） and thermogravimeter-differential scanning calorimeter （TD-DSC） were used to measure the viscosity, structure, molecular weight and thermostability of the prepared products systematically. The results show that the most suitable stuff molar ratio of diol/diacid is 1.14：1, the catalyst dosage used is 0.03% of the raw material used, the reaction temperature is 200-220℃ and the reaction time is 6 h; under above conditions, the products have numberaverage molecular weight （NMW） of 1.90 × 10^3, the distribution index of 1.4 and degree of polymerization n of 10. The decomposed temperatures for the products of poly（1,2-propylene glycol adipate）, poly（1,3-butylene glycol adipate） and poly（1,4-butylene glycol adipate） are 334℃, 349℃ and 358℃, respectively, which indicates that the prepared polyesters have higher thermostability.