As far as we know, to enhance the toughness of poly(L-lactide) (PLLA) without compromising its inherent biodegradability, melt blending PLLA with flexible biodegradable polymers is the most effective and universal method. However, most of research results show a slight improvement in impact toughness due to the amorphous PLLA matrix. In other words, effective impact toughness can be achieved only if PLLA blend is in a highly crystalline state. In this work, blend of PLLA with 20 wt% PCL was prepared and then samples made by injection molding were applied to thermal annealing at different temperatures for 2 h to increase the crystallinity of PLLA matrix. The results show that the crystallinity of PLLA/PCL blend annealing at 80 °C is exceeding 40% and impact strength of the samples increases from 5.92 KJ/m² of unannealed neat PLLA to 26.81 KJ/m². At the same time, the thermal properties are also improved by a large margin.

据我们所知，要提高聚（L-丙交酯）（PLLA）的韧性而不损害其固有的生物降解性，将PLLA与柔性可生物降解的聚合物熔融共混是最有效和通用的方法。但是，大多数研究结果表明，由于非晶质PLLA基体的影响，冲击韧性略有提高。换句话说，仅当PLLA共混物处于高度结晶状态时，才能获得有效的冲击韧性。在这项工作中，制备了PLLA与20 wt％PCL的共混物​​，然后将通过注塑成型制成的样品在不同温度下进行热退火2小时，以提高PLLA基体的结晶度。结果表明，PLLA / PCL共混物在80°C退火时的结晶度超过40％，样品的冲击强度从5.92 KJ / m ^2增加未退火的纯PLLA的最大拉伸强度为26.81 KJ / m ²。同时，热性能也大大提高。