In this work, a series of highly branched linear-comb random copolyesters of ε-caprolactone (CL) and δ-valerolactone (VL) with high molecular weight and narrow distribution in various compositions were successfully synthesized. The composition-dependent microstructure, thermal and mechanical properties, and enzymatic degradation behavior of the resulting copolyesters were investigated systematically. The cocrystallization behavior was observed for the highly branched linear-comb random CL/VL copolyesters over the entire composition range, and a pseudo-eutectic point of isodimorphism occurred at about 50 mol% VL incorporated in copolymer. The obtained copolymers displayed lower Young's modulus, yield strength, and breaking strength, but higher elongation at break. Furthermore, the copolymers presented much higher degradation rate during enzymatic degradation process in comparison with parent homopolymers. More importantly, it was found that both mechanical properties and degradation behavior showed a similar pseudo-eutectic behavior of isodimorphism. Consequently, the correlation among of isodimorphism, mechanical properties, and degradation behavior depending on composition is highly significant, and the physical properties and degradation rate of the isodimorphic copolyesters could be continuously tailored by the feedstocks.

在这项工作中，成功地合成了一系列高分子量，窄分布的ε-己内酯（CL）和δ-戊内酯（VL）的高支化线性梳状无规共聚酯。系统研究了取决于组成的微观结构，热和机械性能以及所得共聚酯的酶促降解行为。在整个组成范围内观察到高度支化的线性梳状无规CL / VL共聚酯的共结晶行为，并且在共聚物中掺入约50mol％的VL时发生了同晶的拟共晶点。所得共聚物显示出较低的杨氏模量，屈服强度和断裂强度，但是断裂伸长率较高。此外，与母体均聚物相比，该共聚物在酶促降解过程中呈现出更高的降解速率。更重要的是，发现机械性能和降解行为都表现出类似的同晶的拟共晶行为。因此，取决于组成，同晶相，机械性能和降解行为之间的相关性非常显着，并且可以通过原料连续调整同晶相共聚酯的物理性能和降解速率。