Preparation of W/W emulsion gels based on chitosan and carboxymethyl cellulose via associative phase separation

In this work, we prepared the W/W emulsion gels based on chitosan (CS) and carboxymethyl cellulose (CMC) via associative phase separation without adding any extra stabilizers. The W/W emulsion gels system with different M CS /M CMC ratios (3:1, 2:1, 1:1, 1:2, 1:3, w/w) and concentrations (1 %, 1.25 %, 1.5 %, 1.75 %, w/v) were prepared, and their corresponding properties were further investigated in the present work. FTIR demonstrated that the formation of W/W emulsion gels was driven by electrostatic interactions and hydrogen bond interactions. The CLSM results confirmed that three types of W/W emulsion gels were formed in the prepared systems, and SEM results further suggested that the gel system with 1:1 M CS /M CMC ratio was belonging to W/W emulsion droplet-aggregated gels. Moreover, for the prepared gel systems, the W/W emulsion droplet-aggregated gels with 1.5 % polymer concentration and 1:1 M CS /M CMC ratio showed the most uniform three-dimensional network structure, the best rheological and mechanical properties, as well as the highest swelling ratio. Overall, these findings provide new reference for the preparation of W/W emulsion gels based on associative phase separation without adding any extra stabilizers.