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The Structure, Functions, and Mechanical Properties of Keratin

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Abstract

Keratin is one of the most important structural proteins in nature and is widely found in the integument in vertebrates. It is classified into two types: α-helices and β-pleated sheets. Keratinized materials can be considered as fiber-reinforced composites consisting of crystalline intermediate filaments embedded in an amorphous protein matrix. They have a wide variety of morphologies and properties depending on different functions. Here, we review selected keratin-based materials, such as skin, hair, wool, quill, horn, hoof, feather, and beak, focusing on the structure–mechanical property-function relationships and finally give some insights on bioinspired composite design based on keratinized materials.

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Acknowledgements

We thank James Kiang for help with the feathers and Christy Chao for help with the quills. This work is supported by Research Grant 1006931 from the National Science Foundation, Division of Materials and Grant 100-2218-E-007-016-MY3 from the Taiwan National Science Council.

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Authors and Affiliations

  1. Department of Mechanical and Aerospace Engineering, UC San Diego, La Jolla, CA, 92093, USA

    J. McKittrick & M. A. Meyers

  2. Materials Science and Engineering Program, UC San Diego, La Jolla, CA, USA

    J. McKittrick, S. G. Bodde, W. Yang, E. E. Novitskaya & M. A. Meyers

  3. Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan, ROC

    P.-Y. Chen

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  1. J. McKittrick
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Correspondence to J. McKittrick.

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McKittrick, J., Chen, PY., Bodde, S.G. et al. The Structure, Functions, and Mechanical Properties of Keratin. JOM 64, 449–468 (2012). https://doi.org/10.1007/s11837-012-0302-8

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