Bioinspired Bouligand cellulose nanocrystal composites: a review of mechanical properties

Bharath Natarajan; Jeffrey W Gilman

doi:10.1098/rsta.2017.0050

Bioinspired Bouligand cellulose nanocrystal composites: a review of mechanical properties

Philos Trans A Math Phys Eng Sci. 2018 Feb 13;376(2112):20170050. doi: 10.1098/rsta.2017.0050.

Authors

Bharath Natarajan^{1

2}, Jeffrey W Gilman³

Affiliations

¹ Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
² Department of Physics, Georgetown University, Washington, DC 20057, USA.
³ Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA jwgilman@nist.gov.

Abstract

The twisted plywood, or Bouligand, structure is the most commonly observed microstructural motif in natural materials that possess high mechanical strength and toughness, such as that found in bone and the mantis shrimp dactyl club. These materials are isotropically toughened by a low volume fraction of soft, energy-dissipating polymer and by the Bouligand structure itself, through shear wave filtering and crack twisting, deflection and arrest. Cellulose nanocrystals (CNCs) are excellent candidates for the bottom-up fabrication of these structures, as they naturally self-assemble into 'chiral nematic' films when cast from solutions and possess outstanding mechanical properties. In this article, we present a review of the fabrication techniques and the corresponding mechanical properties of Bouligand biomimetic CNC nanocomposites, while drawing comparison to the performance standards set by tough natural composite materials.This article is part of a discussion meeting issue 'New horizons for cellulose nanotechnology'.

Keywords: Bouligand; cellulose nanocrystals; chiral nematic; extrinsic toughening; nanocomposites; self-assembly.

Publication types

Review