Nanoconfinement controls stiffness, strength and mechanical toughness of beta-sheet crystals in silk.

@article{Keten2010NanoconfinementCS,
  title={Nanoconfinement controls stiffness, strength and mechanical toughness of beta-sheet crystals in silk.},
  author={Sinan Keten and Zhiping Xu and Britni Ihle and M. Buehler},
  journal={Nature materials},
  year={2010},
  volume={9 4},
  pages={
          359-67
        }
}
Silk features exceptional mechanical properties such as high tensile strength and great extensibility, making it one of the toughest materials known. The exceptional strength of silkworm and spider silks, exceeding that of steel, arises from beta-sheet nanocrystals that universally consist of highly conserved poly-(Gly-Ala) and poly-Ala domains. This is counterintuitive because the key molecular interactions in beta-sheet nanocrystals are hydrogen bonds, one of the weakest chemical bonds known… 

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