Boron equilibria with high molecular weight guar: An NMR study

Reaction Kinetics and Subsequent Rheology of Carboxymethyl Guar Gum Produced from Guar Splits

“…Borate cross-linkers are widely used for fracturing fluids because of their characteristics as pH-sensitive reversible cross-links for hydroxyl groups . At pH values between 8.5 and 12 the material is cross-linked, while at low pH the material is not cross-linked.…”

Borate‐Mediated Stereo‐ and Topo‐Selective Methylation of 1,4‐β‐Glucomannan

“…For G, the 65% average increase of DS is the result of +93% for O‐2, +108% for O‐3, and only +25% for O‐6. Previous studies have shown that crosslink density depends on temperature, since the complex formation between polysaccharide and B(OH) 4 – in water is exothermic and the equilibrium constant decreases with increasing temperature . From the results of their molecular dynamic simulation study of the KGM‐borate complex in water Jian et al proposed that at elevated temperature the crosslinking site between 6‐OH at G and B(OH) 4 – is maintained .…”

“…When NaOH was added, viscosity decreases. Due to the chain–chain interaction, borate‐ cis ‐diols crosslinks are assumed to be more favored with M from M‐rich areas than with M adjacent to G . Borate complexation (B) is a dynamic process.…”

Charge regulation enables anionic hydroxypropyl guar-borate adsorption onto anionic and cationic polystyrene latex

“…Under the conditions of our experiments we estimate that the average number of bound borate groups per sugar ring is 0.34, assuming Jasinski's binding constant of 100 L/mol, and only binding to galactose [19]. Nevertheless, the results in Fig.…”