Ambient-condition curable high internal phase emulsion as a 3D-printable and scalable porous template

Abstract

High internal phase emulsion (HIPE) presents an attractive approach for fabricating porous materials, however, most of which require external energy input (e.g., heat, UV) to solidify soft colloid templates into robust polymeric skeleton structures. Herein, a ketone-group-containing ambient-condition curable (ACC) copolymer was prepared in order to create a polyHIPE system based on the keto-hydrazide chemistry. Tailored design is made possible by the adaptable construction feature of ACC copolymer, and its amphiphilic properties significantly expand the selection of water-in-oil (W/O) HIPE stabilizers. By utilizing the unmodified ZnO nanoparticles as stabilizers and anti-shrinkage agents based on ionic crosslinking, and employing the ACC copolymer solution as the continuous phase, we streamlined the stabilization modification step, removed the need for purifying polyHIPE, and established a rapid, straightforward, and cost-effective polyHIPE preparation protocol. Results demonstrated that the obtained polyHIPEs exhibit ideal pore structures, with densities as low as 0.046 g/cm³ and porosities exceeding 90%, exhibiting remarkable stability, 3D printing feasibility, and the capacity for crosslinking under ambient circumstances. By using Soxhlet extraction, the gel content of polyHIPEs was found to be 65.5%, and mechanical characteristics were assessed up to 1.9 MPa. The technique’s successful 20-fold scaled-up HIPE production further confirms it as a promising and straightforward approach for large-scale, energy-saving, and environmentally friendly manufacture of self-curable HIPEs.