(434d) Enhancing Dispersion Stability of Alpha-1,3-Glucan Using Adipic Acid Derivatization: A Novel Approach for Industrial Applications

Polysaccharides play a crucial role in many industrial applications and are of renewed interest as sustainable material options. However, polysaccharides typically face challenges related to dispersion stability and processing characteristics. Derivatized polysaccharides, with charged surfaces, often have improved dispersion stability. These charged polysaccharides may include carboxymethylcellulose, (CMC) and carboxymethyl glucan (CMG). This work investigates the utilization of polysaccharide esters made from alpha-1,3-glucan and adipic acid, a dicarboxylic acid, to impart charge on the resulting polysaccharide surface. The method is designed to selectively derivatize surface sites of insoluble particles. Unlike CMC and CMG which are polysaccharide-ethers, these anionic glucan esters, exhibit improved thermal stability (decomposition temperature = ~240 °C versus CMG = ~210 °C) and maintain commendable dispersion stability (zeta potential as low as -13.00 mV). Solid-state NMR spectroscopy via the magic-angle-spinning, direct excitation method is promoted for quantitative analysis of degree of substitution. The study demonstrates colloidal particle dispersion with attributes amenable to practical applications of these new alpha-1,3-glucan esters in areas such as home and personal care applications.