Ultrastrong composites from dopamine modified-polymer-infiltrated colloidal crystals

Liaqat, F. et al. (2015) Ultrastrong composites from dopamine modified-polymer-infiltrated colloidal crystals. Materials Horizons, 2(4), pp. 434-441. (doi: 10.1039/C5MH00016E)

Abstract

Although strong and stiff synthetic composites have long been developed, the microstructure of today's most advanced composites has yet to achieve the sophisticated hierarchy of hybrid materials built up by living organisms. We have assembled hard and tough multilayered nanocomposites, which contain alternating layers of Fe3O4 nanoparticles and a 3-hydroxy-tyramine (dopamine) substituted polymer (dopamine modified polymer), strongly cemented together by chelation through infiltration of the polymer into the Fe3O4 mesocrystal. With a Young's modulus of 17 ± 3 GPa and a hardness of 1.3 ± 0.4 GPa the nanocomposite exhibits high resistance against elastic as well as plastic deformation. Key features leading to the high strength are the strong adhesion of the polymer to the inorganic nanoparticles and the layered assembly.

• Item Type: Articles (Other)
• Additional Information: Finding pathways to synthetic analogs of nacre or bones represents a fundamental milestone in the development of composite materials. The brick and- mortar arrangement of inorganic and organic layers is believed to be the most essential strength- and toughness-determining structural feature of nacre. It has also been found that the crosslinking by tightly folded macromolecules is equally important. When the binding of this polymer is weak, flexible composites are obtained, whereas strongly binding polymers may lead to hard composites. Here we demonstrate that both structural features of nacre can be reproduced by sequential deposition of Fe3O4 nanoparticles and “sticky” polymers. This simple process leads to a nanoscale analogue of nacre with alternating inorganic and organic layers, where the polymer infiltrates the Fe3O4 mesocrystal, thereby cementing together the individual particles by chelation. The structural and functional resemblance makes the particle–polymer composite a close replica of natural biocomposites whose nanoscale nature enables elucidation of molecular processes occurring under stress.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Liaqat, Dr Faroha
• Authors: Liaqat, F., Tahir, M. N., Huesmann, H., Daniel, P., Kappl, M., Auernhammer, G. K., Schneider, D., Lieberwirth, I., Char, K., Fytas, G., Butt, H.-J., and Tremel, W.
• College/School: College of Science and Engineering > School of Engineering > Biomedical Engineering
• Journal Name: Materials Horizons
• Publisher: Royal Society of Chemistry
• ISSN: 2051-6347
• ISSN (Online): 2051-6355
• Copyright Holders: Royal Society of Chemistry