聚乳酸在剪切作用下的结晶行为研究进展

综述了剪切作用对聚乳酸（PLA）结晶动力学、晶体形态和晶型的影响；可以看出剪切对PLA的结晶动力学有显著的促进作用，如缩短结晶诱导时间，提高晶核生长速率并最终提高PLA的结晶度；施加剪切作用时，PLA得到的晶体主要是点晶、柱晶甚至串晶，说明剪切对PLA晶体形态有显著的改善作用；剪切也能促使PLA进行α′-α相转变，即对其晶体结构的完善产生积极影响。

Research Progress in Crystallization of Polylactide Under Shear Effects

This paper reviewed the studies on the effects of shear on crystallization kinetics, crystal morphology and crystal structure of polylactide (PLA). These studies indicated that the crystallization kinetics of PLA was improved remarkably by shearing effect, for example, the crystallization induce time was reduced and the nuclei growth rate was improved, thus leading to an increase in crystallinity of PLA. Moreover, the point-like, row-like and even shisi-like crystals could be formed for PLA under shear. This suggests that the crystalline morphology of PLA can be improved under shear. The shear effect can also result in a phase transition from α′-form crystals to the α-form one and, therefore, makes the crystal structure more perfect.