Amorphous supramolecular structure of carboxymethyl cellulose in aqueous solution at different pH values as determined by rheology, small angle X-ray and light scattering

摘要: Carboxymethyl cellulose (CMC) is one of the most widely used thickening agents in industry. The combination small-angle X-ray scattering (SAXS), static and dynamic light scattering, as well viscosity measurements microscopy at different pH values was utilized to explore physicochemical properties CMC on a scale ranging from individual macromolecules supramolecular assemblies. structure represented set characteristic sample subspaces based SAXS data utilizing string-of-beads model. results indicate that 7.0 molecules are approximately uniformly distributed owing strong intra- intermolecular repulsive interactions. expanded value pKa, where it has largest radius gyration, persistence length, size heterogeneous regions. Below pKa majority volume belongs low density subspaces. Most molecules, however, reside few high Dynamically, composed fast diffusive relaxation processes embedded background non-diffusive slow process mostly pH. rheological were directly related aqueous environment.