The Polymer Society of Korea

Abstract

Water-in-water (W/W) emulsions are attractive for their biocompatibility and selective molecular partitioning, but their instability and limited structural control hinder practical applications. Here, we report a strategy to fabricate structurally tunable all-aqueous gels by stabilizing high-internal-phase W/W emulsions (HIPEs) and photopolymerizing their continuous phase. By addressing depletion-induced particle aggregation using polymer-grafted colloids, we achieve stable HIPEs with >95% internal phase volume. These enable in situ gelation with controllable interconnectivity by tuning particle type and concentration. Systems stabilized with PEG-grafted silica particles form interconnected networks, while polystyrene-based systems yield closed morphologies, affecting molecular diffusion. The resulting gels exhibit tunable viscoelasticity, spreading behavior, and molecular transport properties, and are compatible with diverse monomers and crosslinkers.