Borate-polyol gels

In these hydrogels, the number of crosslinks is determined by the ehemi-cal equilibrium among boric acid, borate ions, and diol sites on the polymer chains, which can be influenced by both temperature and pH. Therefore, pH and temperature can dramatically affect the viscoelastic behavior of the borate-polyol gels. The sol-gel transition typically occurs at pH 8-9, near the pAa of the boron compound. The formation of the crosslink is exothermic, between 1-2 kj mol so that gel formation can be opposed by heating. ... 

Similar to borate-polyol gels, the interpolymer complex gels based on boronate-diol interactions also show pH- and temperature-dependent behaviors. Kiser et synthesized interpolymer complex gels using a pair... 

The ability of borax to induce certain polyols, notably PVA and mannose-containing polysaccharides such as guar gum, to form gels has been known as early as the last century [8, 42-44]. Guar gum-borate is used in tertiary oil recovery, while PYA-borate is commonly used as an adhesive and it is sold as a plaything referred to as sKme for children. 

Borate buffers should not be used in the presence of polyols, including carbohydrates and their derivatives, with which they may form chelate compounds they react in this way with many respiratory intermediates. Use of borate buffers in gel electrophoresis of proteins can result in spreading of the zones if fructose, ribose, sorbitol, catechol or other appropriate polyols are present to form borate complexes (Lerch and Stegemann, 1969). The increased solubility of adrenalin in borate buffers is due to complex formation as is also the improved separation of sugar phosphates chromatographically in the presence of borate buffers. Likewise, complexation of carbohydrates in german-ate or borate buffers is the basis of a suggested method for... 

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