Accelerated crystallization of poly(L-lactic acid) by silk fibroin nanodisc
Accelerated crystallization of poly(L-lactic acid) by silk fibroin nanodisc
复制标题
DOI：
10.1038/s41428-019-0229-9
复制
发表时间：
2019-11-01
期刊：
影响因子：
2.8
通讯作者：
Sakurai, Shinichi
中科院分区：
文献类型：
--
作者：
Pandey, Amit Kumar;Katiyar, Vimal;Sakurai, Shinichi
聚l -乳酸（PLLA）结晶缓慢，其热性能和力学性能不足，限制了PLLA的广泛应用。在本研究中，一种生物基填料——丝素纳米盘（SFN）被加入到PLLA基质中，目的是加速PLLA的结晶过程。通过偏光显微镜（POM）观察和差示扫描量热法（DSC）测量，详细研究了SFN包合物对PLLA结晶性的影响。在DSC等温结晶研究中，为了避免在冷却过程中成核，从熔体到结晶温度进行了极快的冷却（类似300℃/min）。实验结果表明，少量的SFN（仅1%）可以显著提高PLLA的结晶性。SFN的加入对PLLA的玻璃化转变温度和熔融温度没有影响。然而，成核速率和最终结晶度显著提高。本研究利用两种不同类型的PLLA (D片段含量分别为0.5和1.4%)，考察了光学纯度对SFN加速能力的影响。结果发现，在高光学纯PLLA （0.5% D部分）的情况下，增强程度要大得多。
Slow crystallization of poly(L-lactic acid) (PLLA) limits the widespread applications of PLLA because of its insufficient thermal and mechanical properties. In this study, a biobased filler, silk fibroin nanodisc (SFN), has been included in the PLLA matrix with the aim of accelerating the crystallization process of PLLA. Detailed investigation of the effect of SFN inclusion on the crystallizability of PLLA has been performed by polarizing optical microscope (POM) observations and differential scanning calorimetry (DSC) measurements. For isothermal crystallization studies by DSC, extremely quick cooling (similar to 300 degrees C/min) from the melt to the crystallization temperature was conducted in order to avoid nucleation during the cooling process. The experimental results show that the small amount of SFN (only 1%) can significantly enhance the crystallizability of PLLA. The glass transition temperature and the melting temperature of PLLA were not influenced by the inclusion of SFN. However, the nucleation rate and the final degree of crystallinity were significantly enhanced. The effect of optical purity on the acceleration ability of SFN was examined in this research by utilizing two different types of PLLA having different contents of the D moiety (0.5 and 1.4%). As a result, it was found that the extent of enhancement is much larger in the case of highly optical pure PLLA (0.5% D moiety).