Institute of Fine Organic Chemistry and New Organic Materials, Wuhan University of Science and Technology, Wuhan 430081, China.
Department of Petroleum Engineering, Applied Chemistry in Oil and Gas Fields, Yangtze University, Wuhan 430100, China.
Molecules. 2022 Jan 5;27(1):325. doi: 10.3390/molecules27010325.
In this work, the feasibility of replacing petroleum-based poly(ethylene terephthalate) (PET) with fully bio-based copolyesters derived from dimethyl 2,5-thiophenedicarboxylate (DMTD), dimethyl 2,5-dimethoxyterephthalate (DMDMT), and polysaccharide-derived 1,6-hexanediol (HDO) was investigated. A systematic study of structure-property relationship revealed that the properties of these poly(thiophene-aromatic) copolyesters (PHS(20-90)) can be tailored by varying the ratio of diester monomers in the reaction, whereby an increase in DMTD content noticeably shortened the reaction time in the transesterification step due to its higher reactivity as compared with DMDMT. The copolyesters had weight-average molar masses (Mw) between 27,500 and 38,800 g/mol, and dispersity Đ of 2.0-2.5. The different polarity and stability of heterocyclic DMTD provided an efficient mean to tailor the crystallization ability of the copolyesters, which in turn affected the thermal and mechanical performance. The glass transition temperature (T) could be tuned from 70-100 °C, while the tensile strength was in a range of 23-80 MPa. The obtained results confirmed that the co-monomers were successfully inserted into the copolyester chains. As compared with commercial poly(ethylene terephthalate), the copolyesters displayed not only enhanced susceptibility to hydrolysis, but also appreciable biodegradability by lipases, with weight losses of up to 16% by weight after 28 weeks of incubation.
在这项工作中，研究了用完全基于生物的共聚酯替代石油基聚对苯二甲酸乙二醇酯（PET）的可行性，这些共聚酯由 2,5-噻吩二甲酸二甲酯（DMTD）、2,5-二甲氧基对苯二甲酸二甲酯（DMDMT）和多糖衍生的 1,6-己二醇（HDO）共聚而成。对结构-性能关系的系统研究表明，这些聚（噻吩-芳族）共聚酯（PHS（20-90））的性能可以通过改变反应中两种二酯单体的比例来调整，由于 DMTD 的反应性比 DMDMT 高，因此其含量的增加显著缩短了酯交换反应步骤的反应时间。共聚酯的重均摩尔质量（Mw）在 27500 至 38800g/mol 之间，分散度 Đ 为 2.0-2.5。杂环 DMTD 的不同极性和稳定性提供了一种有效的方法来调整共聚酯的结晶能力，从而影响其热性能和机械性能。玻璃化转变温度（T）可从 70-100°C 进行调节，而拉伸强度则在 23-80MPa 的范围内。所得结果证实了共单体成功地插入到共聚酯链中。与商业聚对苯二甲酸乙二醇酯相比，共聚酯不仅对水解的敏感性增强，而且对脂肪酶的生物降解性也相当可观，在 28 周的孵育后，重量损失高达 16%。
