DSC and SWAXS Studies on the Effects of Silk Nanocrystals on Crystallization of Poly(l-Lactic Acid)

  • Amit Kumar Pandey
  • Pham Thi Ngoc Diep
  • Rahul Patwa
  • Vimal Katiyar
  • Sono Sasaki
  • Shinichi SakuraiEmail author
Part of the Materials Horizons: From Nature to Nanomaterials book series (MHFNN)


Poly (l-lactic acid) (PLLA) is one of the most frequently used biobased polyesters due to its favorable mechanical properties. However, some properties such as slow crystallization rate and low crystallinity restrict its commercial uses. In order to overcome these limitations, organic nanofillers are incorporated into the PLLA matrix. Herein, we report the use of silk nanocrystal (SNC) as a solid-state nucleation agent, which has been prepared in the laboratory from the wastes of the muga silk cocoon. PLLA/SNC composites with 1.0 wt% loadings of SNC have been prepared by solution casting with dichloromethane as a cast solvent. Isothermal crystallization kinetics at 110 °C has been studied by the differential scanning calorimetry (DSC) and small- and wide-angle X-ray scattering (SWAXS) upon quenching from melt (200 °C for 5 min). As a result, it is found that loading SNC with 1.0 wt% caused the reduction of the induction period, the acceleration of crystallization, the increase of the final value of the degree of crystallinity, and the acceleration of lamellar thickening. These experimental results can be explained by the fact that the regular folding of the polymer chains is attained by the loading of SNC.


Poly (l-lactic acid) Silk nanocrystal Small- and wide-angle X-ray scattering Crystallization 


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© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • Amit Kumar Pandey
    • 1
  • Pham Thi Ngoc Diep
    • 1
  • Rahul Patwa
    • 2
  • Vimal Katiyar
    • 2
  • Sono Sasaki
    • 1
  • Shinichi Sakurai
    • 1
    Email author
  1. 1.Department of Biobased Materials ScienceKyoto Institute of TechnologyKyotoJapan
  2. 2.Department of Chemical EngineeringIndian Institute of Technology GuwahatiGuwahatiIndia

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