Journal Article

Self-shaping composites with programmable bioinspired microstructures

Sander, Jonathan S., Studart, André R., Erb, Randall M., Grisch, Roman

2013

Overview

Shape change is a prevalent function apparent in a diverse set of natural structures, including seed dispersal units, climbing plants and carnivorous plants. Many of these natural materials change shape by using cellulose microfibrils at specific orientations to anisotropically restrict the swelling/shrinkage of their organic matrices upon external stimuli. This is in contrast to the material-specific mechanisms found in synthetic shape-memory systems. Here we propose a robust and universal method to replicate this unusual shape-changing mechanism of natural systems in artificial bioinspired composites. The technique is based upon the remote control of the orientation of reinforcing inorganic particles within the composite using a weak external magnetic field. Combining this reinforcement orientational control with swellable/shrinkable polymer matrices enables the creation of composites whose shape change can be programmed into the material’s microstructure rather than externally imposed. Such bioinspired approach can generate composites with unusual reversibility, twisting effects and site-specific programmable shape changes. Many living organisms use materials that are capable of changing their shape in response to changes in the environment. Erb et al . demonstrate an approach to synthesizing artificial shape-changing composites that replicate such behaviour.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 639/301/54/989 / Biomimetic Materials - chemistry / Cellulose / Humanities and Social Sciences / Magnetic fields / multidisciplinary / Pinus - embryology / Polymers / Polymers - chemistry / Remote control / Science / Science (multidisciplinary) / Seed dispersal / Seeds