The effect of post-processing annealing beyond the glass transition temperature on optical transparency was studied using poly(lactic acid) (PLA) films containing a nucleating agent such as N,N′-ethylenebis(stearamide) (EBS) or N,N′-ethylenebis(12-hydroxystearamide) (EBHS). Although the PLA films without the nucleating agent became opaque after exposure to annealing, the film with an appropriate amount of the nucleating agent was found to be transparent (the haze value was lower than 10%). Since the crystallinity was enhanced by annealing, the film showed excellent heat resistance. As compared with EBS, moreover, EBHS had a better capability to produce a transparent film because the aggregates, which appeared during cooling from the molten state, were small. In the case of EBHS, a network structure of fibrous EBHS in molten PLA was confirmed, which was responsible for the reduced size of the PLA crystals and prevented spherulite formation.

使用包含成核剂（例如N，N'-乙撑双硬脂酰胺（EBS）或N，N'）的聚乳酸（PLA）薄膜研究了超过玻璃化转变温度的后退火工艺对光学透明性的影响-亚乙基双（12-羟基硬脂酰胺）（EBHS）。尽管没有成核剂的PLA膜在暴露于退火后变得不透明，但是发现具有适量成核剂的膜是透明的（雾度值低于10％）。由于通过退火提高了结晶度，因此该膜显示出优异的耐热性。此外，与EBS相比，EBHS具有更好的透明膜生产能力，因为从熔融态冷却期间出现的聚集体很小。在EBHS的情况下，证实了熔融的PLA中的纤维状EBHS的网络结构，这导致PLA晶体的尺寸减小并且防止了球晶的形成。