Symmetry breakdown in the sol-gel transition of a Guar gum transient physical network

Abstract

The gelation of the mixture of guar gum and borax in an aqueous solution was studied by diffusing-wave spectroscopy microrheology. The Winter and Chambon power-law domain was evidenced at high-frequency range. The time-cure superposition was applied to the mean square displacement of the probe particles and the critical power-law behavior of the shifting factors was revealed close to the percolation threshold. Morphological characterization revealed the emergence of ribbon-like structures at high borax concentrations. The Rubinstein and Semenov plateau was demonstrated. The correlations between the critical exponents that govern the gelation of the transient networks were reviewed with regard to the scaling laws of both permanent and transient networks. Unlike permanent networks, the relation n+= n- was assumed as the unique condition to establish the hyperscaling laws in transient networks. Whereas, the symmetry breakdown of the longest relaxation time was found to be a common feature of the flowable gels.