Wet‐spun porous fibers from high internal phase emulsions: Continuous preparation and high stretchability

Abstract

Although high internal phase emulsion (HIPE)-templating is promising to prepare macroporous materials (polyHIPEs) with controllable shapes and tuneable property, fibrous polyHIPEs with stretchability and their continuous preparation are still challenging. Here, we report the fabrication of polyHIPE fibers in a continuous manner through wet spinning of HIPEs. The successful fabrication of polyHIPE fibers depends on HIPE dispersed phase fractions, ammonia-catalyzed interfacial reaction and wet spinning. Dry polyHIPE fibers exhibit tunable diameters, hierarchically porous structures, high stability to temperature and to various solutions, and high stretchability (with a high tensile strain of 155%), which is hard to achieve for polyHIPEs. The polyHIPE fibers show enhanced uptakes to both water (14.4 ml g −1 ) and organic solvents (up to 26.3 ml g −1 ), and the amphiphilic swelling is rare for polyHIPEs. Moreover, the dry polyHIPE fibers show good thermal insulation, similar to that of cotton. Simple wet spinning, combining with HIPEs with tuneable composition, is promising for preparing various polyHIPE fibers for various potential applications.

A Review of the Preparation of Porous Fibers and Porous Parts by a Novel Micro-Extrusion Foaming Technique

“…In recent years, advancements in equipment and deepening research have given rise to new methods for fabricating porous fibers, garnering significant attention. Notably, high internal phase emulsion template methods [ 50 , 51 , 52 ], coaxial wet spinning [ 25 , 53 ], freeze spinning [ 6 , 13 , 54 ], and microfluidic spinning [ 37 , 55 ] have gained prominence. Among them, wet spinning refers to a molding method where the spinning solution is extruded into a coagulation bath through a syringe, resulting in the solidification of the polymer into porous fibers through a double-diffusion process.…”