Pickering high internal-phase emulsions (HIPEs) and porous materials derived from the Pickering HIPEs have received increased attention in various research fields. Nevertheless, nondegradable inorganic and synthetic stabilizers present toxicity risks, thus greatly limiting their wider applications. In this work, we successfully developed nontoxic porous materials through the Pickering HIPE-templating process without chemical reactions. The obtained porous materials exhibited appreciable absorption capacity to corn oil and reached the state of saturated absorption within 3 min. The Pickering HIPE templates were stabilized by gliadin-chitosan complex particles (GCCPs), in which the volume fraction of the dispersed phase (90%) was the highest of all reported food-grade-particle-stabilized Pickering HIPEs so far, further contributing to the interconnected pore structure and high porosity (>90%) of porous materials. The interfacial particle barrier (Pickering mechanism) and three-dimensional network formed by the GCCPs in the continuous phase play crucial roles in stabilization of HIPEs with viscoelastic and self-supporting attributes and also facilitate the development of porous materials with designed pore structure. These materials, with favorable biocompatibility and biodegradability, possess excellent application prospects in foods, pharmaceuticals, materials, environmental applications, and so on.
Keywords: Pickering high internal-phase emulsions; emulsion templating; porous materials.