Scleroglucan and guar gum: The synergistic effects of a new polysaccharide system

Abstract

Scleroglucan (Sclg) and Guar Gum (GG) are both capable to give gels in the presence of borax and this study is focused on how a mixed system of the two polysaccharides can be affected by the addition of borax. The anisotropic swelling behavior of tablets obtained by compression of the freeze-dried new gel system is also investigated and compared to that of Sclg and GG alone. Rheological characterization evidences a synergistic effect in terms of critical time, mesh size, as well as crosslinking density. Also creep recovery experiments, carried out in the presence of borax, show a synergistic effect: when the polymers are mixed, a quite low compliance was estimated in comparison to that of Sclg and GG. On the other side, the flexible chains of GG induce the self-healing properties of the mixed gel system, since the rigid triple helix of Sclg does not show such peculiar characteristics. The deep insight of the physico-chemical properties of the new hydrogel system can play a fundamental role for the optimization of its practical application (e.g., in drug delivery, cosmetic products, human tissue repair, wound dressing and food staff).

Keywords

• biopolymers, biocomposites
• rheology
• low field nmr
• scleroglucan
• guar gum