Multiscale Quantitative Rheological Analysis of Composition-Temperature Relationships in Borate-Guar Hydrogels.

ABSTRACT: Borate-cross-linked guar gum gels exhibit complex viscoelasticity driven by reversible covalent interactions between borate ions and cis-diol groups. Despite their widespread industrial use, limited knowledge of their thermorheological behavior makes it difficult to predict their performance at high temperatures. Here, 0.50 wt % guar gum dispersions with borax-to-guar ratios ranging from 1:1 to 1:8 (i.e., 0.5000-0.0625 wt % borax) were characterized from 25 to 140 °C using oscillatory rheometry. At 25 °C, gels displayed predominantly elastic behavior (G' ≫ G″); above 120 °C, viscous behavior dominated due to thermally induced cross-link dissociation. Time-temperature superposition was valid up to 120 °C, and Arrhenius analysis yielded activation energies of 72-85 kJ mol^-

SUBMITTER: Martin-Alfonso MJ 

PROVIDER: S-EPMC12707247 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature