Biobased poly(ethylene succinate)-b-poly(triethylene terephthalate) (PES-b-PTEGT) multiblock copolyesters with low weight ratios of PTEGT segment were successfully synthesized from dihydroxyl terminated PES and dihydroxyl terminated PTEGT prepolymers in this work through a chain extension reaction. The thermal, crystallization, and mechanical properties of PES-b-PTEGT were systematically investigated and compared with those of PES also prepared via the chain extension method. Two glass transition temperature (T_g) values were detected for PES-b-PTEGT, corresponding to the T_g of PES segment and that of PTEGT segment, respectively. PES-b-PTEGT showed a high melting temperature of around 100 °C and a thermal decomposition temperature of above 320 °C. The crystallizability of PES segment in PES-b-PTEGT was obviously enhanced under different crystallization conditions, which was attributed to the interface-assisted crystallization. In addition, the mechanical property (including both the elongation at break and the tensile strength) of PES-b-PTEGT was also remarkably improved. The synthesis of PES-b-PTEGT with a high melting temperature, faster crystallization rate, and improved mechanical property provided a new modification method to improve the physical property and extend the practical application of biodegradable polyesters.

本工作以二羟基封端 PES 和二羟基封端 PTEGT 预聚物为原料，通过扩链反应成功合成了低重量比 PTEGT 链段的生物基聚丁二酸乙二酯-b-聚对苯二甲酸三乙二酯 (PES -b- PTEGT) 多嵌段共聚酯。 . 系统地研究了 PES -b- PTEGT的热、结晶和机械性能，并与同样通过扩链方法制备的 PES 进行了比较。PES-b - _PTEGT检测到两个玻璃化转变温度 ( Tg ) 值，分别对应于PES 链段和 PTEGT 链段的Tg _。PES -b-PTEGT表现出约100°C的高熔融温度和320°C以上的热分解温度。PES-b- PTEGT中PES链段的结晶性在不同结晶条件下明显增强，这归因于界面辅助结晶。此外，PES -b- PTEGT 的力学性能（包括断裂伸长率和拉伸强度）也显着提高。合成具有较高熔融温度、较快结晶速率和改善力学性能的PES -b- PTEGT ，为提高生物降解聚酯的物理性能和拓展实际应用提供了一种新的改性方法。