Biodegradable polylactide (PLA)/poly ($\mathrm{\epsilon }$-caprolactone) (PCL) blend is a well-studied immiscible polymer blend system; however, there is no fundamental understanding of how the dispersed phase morphology controls the thermal stability, and the thermal and mechanical properties of the blend systems. Addressing this research question, a series of PLA/PCL blends were processed using melt-blending technique. The results show that the unique thermal stability of the dispersed PCL domains prolonged the complete degradation process of PLA. Furthermore, altering the activation energies (E_a) of PLA/PCL blends revealed that thermal stability depends not only on the governing mechanism change during degradation process but also on the behavior of phase-separated morphology characteristics. The presence of evenly dispersed PCL particles within PLA matrix enhanced the crystallization rate coefficient of PLA and tailored the spherulite morphologies by acting as a nucleating agent, thus promoting the crystallization ability of PLA chains. Consequently, remarkable increase in elongation at break was achieved for 60PLA/40PCL blend, with well-balance tensile modulus and tensile strength characteristics. Despite the significant storage modulus increase of the blends at low temperatures, significant storage modulus decrease is noted with increasing temperature, due to packing density, chain mobility phenomenon, and unfrozen PCL molecules. The enhanced processability of PLA by ductile PCL, with improved and balanced properties, enables the technological advancement of bio-based PLA for a wide range of applications.

可生物降解的聚丙交酯（PLA）/聚（$\mathrm{\epsilon }$-己内酯）（PCL）共混物是经过充分研究的不混溶的聚合物共混体系；然而，对分散相形态如何控制热稳定性以及共混体系的热和机械性能尚无基本的了解。为了解决这一研究问题，使用熔融共混技术对一系列PLA / PCL共混物进行了加工。结果表明，分散的PCL域的独特热稳定性延长了PLA的完整降解过程。此外，改变活化能（E _a）的PLA / PCL共混物表明，热稳定性不仅取决于降解过程中的控制机理变化，而且还取决于相分离形态特征的行为。在PLA基质中均匀分散的PCL颗粒的存在增强了PLA的结晶速率系数，并通过充当成核剂来调整球晶的形貌，从而提高了PLA链的结晶能力。因此，具有良好平衡的拉伸模量和拉伸强度特性的60PLA / 40PCL共混物的断裂伸长率显着提高。尽管在低温下共混物的储能模量显着增加，但由于堆积密度，链迁移现象和未冻结的PCL分子，随着温度升高，储能模量仍显着下降。