Sustainable biobased terpolyester based on heterocyclic dimethyl furan-2,5-dicarboxylate and isosorbide in combination with ethylene glycol and 1,4-cyclohexanedimethylene (PEICF) were successfully synthesized by two-step melt polymerization method and characterized. A series of PEICF terpolyester exhibited excellent heat resistive properties, with glass transition temperatures of 81–119 °C, and high molecular weights (Mw = 50,800 g mol⁻¹). When esterification was carried out at fixed a COOH:OH molar ratio of 1:2, 1,4-cyclohexanedimethanol (CHDM) showed increased reactivity compared to isosorbide (ISB) and ethylene glycol (EG) monomers. As a result, EG was most likely to be placed at the end of the oligomer chains, which accelerated the transesterification process and drastically increased chain growth via chain scission at the carbonyl carbon adjacent to the ethylene unit due to steric hindrance. The zero shear viscosities of the PEICF terpolyester were much higher than that of the copolyester and increased with increasing ISB content. This study proposed a method for improving the low reactivity of dimethyl furan-2,5-dicarboxylate, which shows suppressed furan ring flipping, with sterically hindered ISB by using highly reactive CHDM at atmospheric pressure. These results signify the importance of controlling the synthetic conditions, as they affect the composition of the polymer backbone due to the different reactivities, volatilities, and steric hindrances of the monomers.

通过两步熔融聚合法成功地合成了基于呋喃-2,5-二羧酸二甲酯和异山梨醇酯与乙二醇和1,4-环己烷二亚甲基（PEICF）的可持续生物基三元聚酯，并对其进行了表征。一系列PEICF三元聚酯表现出优异的耐热性能，玻璃化转变温度为81–119°C，并且分子量高（Mw = 50,800 g mol ^-1）。当固定的COOH：OH摩尔比为1：2进行酯化反应时，与异山梨醇（ISB）和乙二醇（EG）单体相比，1,4-环己烷二甲醇（CHDM）的反应性增强。结果，EG最有可能被置于低聚物链的末端，这由于位阻而加速了酯交换过程，并通过在乙烯单元附近的羰基碳处的断链而急剧增加了链的生长。PEICF三元聚酯的零剪切粘度比共聚酯的零剪切粘度高得多，并且随着ISB含量的增加而增加。这项研究提出了一种通过在大气压下使用高反应性CHDM来提高呋喃2,5-二羧酸二甲酯低反应性的方法，该方法显示出呋喃环的翻转受到抑制，空间位阻了ISB。