Structural Evolution in Isothermal Crystallization Process of Poly(L-lactic acid) Enhanced by Silk Fibroin Nano-Disc

Materials

Sono Sasaki¹  Shinichi Sakurai¹  AmitKumar Pandey¹  Vimal Katiyar²  Nobutaka Shimizu³  Hideaki Takagi³  Noriyuki Igarashi³ 

[1] Department of Biobased Materials Science, Kyoto Institute of Technology, Kyoto 606-8585, Japan;Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India;High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801, Japan;

关键词: poly(L-lactic acid);    silk fibroin nano-disc;    crystalline lamella;    isothermal crystallization;    lamellar stacking;    small-and wide-angle X-ray scattering simultaneous measurement;   

DOI  :  10.3390/ma12111872

来源: DOAJ

【 摘 要 】

The nucleating effect of silk fibroin nano-disc (SFN) on the crystallization behavior of poly(L-lactic acid) (PLLA) was investigated by simultaneous synchrotron small- and wide-angle X-ray scattering measurements. For the isothermal crystallization at 110 °C from the melt, the induction period of the PLLA specimens containing 1% SFN was reduced compared to that of the neat specimens, indicating the acceleration of the nucleation of PLLA. The final degree of crystallinity was also increased, and the crystallization half-time was decreased, which indicates that the overall crystallization process was accelerated. Furthermore, the final value of the crystallite size (the lateral size of the crystalline lamella) was slightly lower for the specimens containing 1% SFN than that for the PLLA neat specimen, although the crystallites started growing much earlier. However, it was found that there was no effect of SFN on the growth rate of the crystallite size. The lamellar thickening process was also accelerated with a clear overshooting phenomenon with the inclusion of 1% SFN. As for the polymorphism, the α’ phase is dominant with about 96%, but a small amount of the α phase (4%) is found to exist. It was found that the SFN can also accelerate the formation of the minor α phase as well as the major α’ phase.

【 授权许可】

Unknown