Effect of curing bath conditions on the morphology and structure of poly(high internal phase emulsion) fibers

The potential of polymerizing high internal phase emulsions (HIPEs) as a simple and environmentally friendly technique to fabricating porous fibers has been demonstrated. Porous fibers with varied microstructure can be created through manipulation of the composition of the curing bath in which the HIPEs are polymerized. Osmotic pressure effects, activated through setting the electrolyte concentration in the curing bath different than that of the aqueous phase within the HIPE, can be used to alter the void size near the periphery of the fiber. Adding initiator to the bath triggers a relatively faster polymerization reaction at the HIPE‐bath interface, which can lock‐in the microstructure before other kinetic effects occur. Including surfactant in the curing bath can affect the HIPE stability and thus the fiber morphology. Porous fibers exhibiting a variety of surface morphologies, ranging from completely closed surfaces to those with 30‐μm voids, have been produced. This new approach enables the possibility of designing porous fibers for different applications via simple manipulation of curing‐bath conditions.