One-pot synthesis of cross-linked sub-micron microgels from pure cellulose via the Ugi reaction and their application as emulsifiers

Abstract

A novel method for obtaining cross-linked microgels of cellulose has been introduced. This method is based on the Ugi four-component condensation in colloidal suspensions of carboxymethylcellulose with a low degree of substitution. Several types of cellulose, including Avicel, cotton linters and filter paper were used as the starting material for the cellulose microgels. Using various processing parameters (polysaccharide concentration, type of crosslink, optimal pH range and temperature) sub-micrometre particles with controlled colloidal properties were obtained. Cellulose microgels have proved to be an effective Pickering emulsifier at low concentrations, forming stable oil-in-water emulsions. This approach provides access to novel stabilizers of emulsions on the basis of one-pot modification of native cellulose.