GAO, X. et al., 2015. Inelastic behaviour of bacterial cellulose hydrogel: in aqua cyclic tests. Polymer Testing, 44, pp. 82 - 92
Hydrogels are finding increasingly broad use, especially in biomedical applications. Their complex structure - a low-density network of microfibrils - defines their non-trivial mechanical behaviour. The focus of this work is on test-based quantification of mechanical behaviour of a bacterial cellulose (BC) hydrogel exposed to cyclic loading. Specimens for the tests were produced using Gluconacetobacter xylinus ATCC 53582 and tested in aqua under uniaxial cyclic loading conditions in a displacement-controlled regime. Substantial microstructural changes were observed in the process of deformation. A combination of qualitative microstructural observations with quantitative force-displacement relations allowed identification of main deformation mechanisms, confirming inelastic behaviour of the BC hydrogel under a loading-unloading-reloading regime. Elastic deformation was accompanied by non-elastic (viscoplastic) deformation in both tension and compression. This study also aims to establish a background for micromechanical modelling of overall properties of BC hydrogels.
This paper was accepted for publication in the journal Polymer Testing and the definitive published version is available at http://dx.doi.org/10.1016/j.polymertesting.2015.03.021