Study of cryostructuring of polymer systems. XIX. On the nature of intermolecular links in the cryogels of locust bean gum

Abstract

In this study of freeze–thaw-induced gelation of aqueous locust bean gum (LBG) solutions we found that gel formation proceeded through at least two kinetic stages. Initially, rather weak spongy cryostructurates were formed as a result of freezing the system, but their strength and thermostability (fusion temperature) could be increased considerably by means of thawing out the system sufficiently slowly. Preparation of LBG cryogels in the presence of chaotropic (urea) and anti-chaotropic (sodium sulfate) substances showed that the major mechanism responsible for stabilization of junction zones in these gel materials was hydrogen bonding. Therefore, use of the agents facilitating formation of hydrogen bonds enabled the gelation of LBG solutions without the need for synergistic polymers or cryogenic treatments. © 2000 Society of Chemical Industry