Abstract
In this communication a mechanism for spider silk strain hardening is proposed. Shear failure of β-sheet nanocrystals is the first failure mode that gives rise to the creation of smaller nanocrystals, which are of higher strength and stiffness. β-sheet unfolding requires more energy than nanocrystal separation in a shear mode of failure. As a result, unfolding occurs after the nanocrystals separate in shear. β-sheet unfolding yields a secondary strain hardening effect once the β-sheet conformation is geometrically stable and acts like a unidirectional fibre in a fibre reinforced composite. The mechanism suggested herein is based on molecular dynamics calculations of residual inter-β-sheet separation strengths against residual intra-β-sheet unfolding strengths.
Original language | English |
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Article number | 015015 |
Journal | Advances in Natural Sciences: Nanoscience and Nanotechnology |
Volume | 5 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Jan 2014 |
Keywords / Materials (for Non-textual outputs)
- Nanocrystals
- Polyalanine poly(Ala)
- Polyglycine poly(Gly)
- Protein structure
- β-sheet