%0 Journal Article
%T Hierarchical cross-linking in physical alginate gels: a rheological and dynamic light scattering investigation
%+ National Interuniversity Consortium of Materials Science and Technology (INSTM )
%+ Matière Molle
%A Larobina, Domenico
%A Cipelletti, Luca
%< avec comité de lecture
%Z L2C:13-222
%@ 1744-683X
%J Soft Matter
%I Royal Society of Chemistry
%P 10005-10015
%8 2013-09-02
%D 2013
%Z 1309.6349
%R 10.1039/c3sm52006d
%Z Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]Journal articles
%X We investigate the dynamics of alginate gels, an important class of biopolymer-based viscoelastic materials, by combining mechanical tests and non-conventional, time-resolved light scattering methods. Two relaxation modes are observed upon applying a compressive or shear stress. Dynamic light scattering and diffusive wave spectroscopy measurements reveal that these modes are associated with discontinuous rearrangement events that restructure the gel network via anomalous, non-diffusive microscopic dynamics. We show that these dynamics are due to both thermal activation and internal stress stored during gelation and propose a scenario where a hierarchy of cross-links with different life times is responsible for the observed complex behavior. Measurements at various temperatures and sample ages are presented to support this scenario.
%G English
%L hal-00874406
%U https://hal.science/hal-00874406
%~ CNRS
%~ L2C
%~ MIPS
%~ UNIV-MONTPELLIER
%~ UM-2015-2021