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Australian Journal of Chemistry Australian Journal of Chemistry Society
An international journal for chemical science
RESEARCH FRONT

Progress Toward Robust Polymer Hydrogels

Sina Naficy A , Hugh R. Brown A B , Joselito M. Razal A , Geoffrey M. Spinks A B C and Philip G. Whitten A C
+ Author Affiliations
- Author Affiliations

A Intelligent Polymer Research Institute and ARC Centre of Excellence in Electromaterials Science, University of Wollongong, Innovation Campus, Squires Way, Fairy Meadow, NSW, 2519, Australia.

B School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia.

C Corresponding authors. Email: gspinks@uow.edu.au; whitten@uow.edu.au

Australian Journal of Chemistry 64(8) 1007-1025 https://doi.org/10.1071/CH11156
Submitted: 20 April 2011  Accepted: 18 July 2011   Published: 19 August 2011

Abstract

In this review we highlight new developments in tough hydrogel materials in terms of their enhanced mechanical performance and their corresponding toughening mechanisms. These mechanically robust hydrogels have been developed over the past 10 years with many now showing mechanical properties comparable with those of natural tissues. By first reviewing the brittleness of conventional synthetic hydrogels, we introduce each new class of tough hydrogel: homogeneous gels, slip-link gels, double-network gels, nanocomposite gels and gels formed using poly-functional crosslinkers. In each case we provide a description of the fracture process that may be occurring. With the exception of double network gels where the enhanced toughness is quite well understood, these descriptions remain to be confirmed. We also introduce material property charts for conventional and tough synthetic hydrogels to illustrate the wide range of mechanical and swelling properties exhibited by these materials and to highlight links between these properties and the network topology. Finally, we provide some suggestions for further work particularly with regard to some unanswered questions and possible avenues for further enhancement of gel toughness.


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