title: Poroelastic mechanical effects of hemicelluloses on cellulosic hydrogels under compression.
abstract: Hemicelluloses exhibit a range of interactions with cellulose, the mechanical consequences of which in plant cell walls are incompletely understood. We report the mechanical properties of cell wall analogues based on cellulose hydrogels to elucidate the contribution of xyloglucan or arabinoxylan as examples of two hemicelluloses displaying different interactions with cellulose. We subjected the hydrogels to mechanical pressures to emulate the compressive stresses experienced by cell walls in planta. Our results revealed that the presence of either hemicellulose increased the resistance to compression at fast strain rates. However, at slow strain rates, only xyloglucan increased composite strength. This behaviour could be explained considering the microstructure and the flow of water through the composites confirming their poroelastic nature. In contrast, small deformation oscillatory rheology showed that only xyloglucan decreased the elastic moduli. These results provide evidence for contrasting roles of different hemicelluloses in plant cell wall mechanics and man-made cellulose-based composite materials.
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
authors: Patricia
authors: P
authors: Lopez-Sanchez
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
authors: Julie
authors: J
authors: Cersosimo
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
authors: Dongjie
authors: D
authors: Wang
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
authors: Bernadine
authors: B
authors: Flanagan
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, School of Chemical Engineering, The University of Queensland, Brisbane, Australia.
authors: Jason R
authors: JR
authors: Stokes
authors: Australian Research Centre, Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
authors: Michael J
authors: MJ
authors: Gidley
mesh_terms: D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002482:Cellulose / Q000737:chemistry*; D019245:Compressive Strength; D003460:Crystallization; D004548:Elasticity; D005936:Glucans / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D011134:Polysaccharides / Q000737:chemistry*; D013314:Stress, Mechanical; D014783:Viscosity; D014990:Xylans / Q000737:chemistry
chemical_list: D005936:Glucans; D020100:Hydrogels; D011134:Polysaccharides; D014990:Xylans; C029353:xyloglucan; C007916:hemicellulose; D002482:Cellulose; C085118:arabinoxylan