Comparing the properties of Bombyx mori silk cocoons against sericin-fibroin regummed biocomposite sheets

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Alexander Morin, Parvez Alam
Publication year: 2016
Journal: Materials Science and Engineering: C
Volume number: 65
Start page: 215
End page: 220
eISSN: 1873-0191


Abstract

This paper considers the utility of sericin, a degumming waste product, in the regumming of Bombyx mori silk fibroin fibres to form sericin-fibroin biocomposites. Regummed biocomposites have a chemical character that is somewhat closer to fibroin than sericin, though sericin presence is confirmed through FT-IR spectroscopy. Using direct measurements we further find the weight fractions of sericin in the regummed biocomposites and the native cocoons differ by only 5%. Mechanically, B. mori cocoons exhibit brittle stress-strain characteristics, failing at strengths of View the MathML sourceX̅= 16.6 MPa and at strains of View the MathML sourceX̅= 13%. Contrarily, aligning fibroin fibres to a unidirectional axis in the regummed biocomposites causes them to exhibit characteristics of strain hardening, which is itself a typical characteristic of silk fibre pulled in tension. Though they are half as strong (View the MathML sourceX̅= 7.2 MPa), regummed biocomposites are able to absorb five times more mechanical energy (View the MathML sourceX̅= 5.6 MJm− 3) than the B. mori cocoons (View the MathML sourceX̅= 1.1 MJm− 3) and are furthermore able to elongate to more than ten times (View the MathML sourceX̅= 180%) that of the native cocoons prior to failure. Our research shows that degummed B. mori cocoons can be regummed into sheets that have potential for use as load bearing engineering biocomposites.

Last updated on 2019-15-11 at 04:09