Electroactive, elastomeric, microfiber mats that show controllable pore size variation upon electrochemical stimulation are produced from semi-interpenetrating polymer networks (s-IPNs). This type of porous, elastomeric scaffolds that are mechanically dynamic under electrochemical stimuli could find new applications in stretchable electronics, (bio)filtration, soft robotics and stimulation of biological cells.These microfiber mats are prepared in two simple steps. Firstly, a mixture of high molecular weight nitrile butadiene rubber (NBR) and cross-linking agent, poly(ethylene glycol)dimethylacrylate are electrospun with in situ cross-linking. Secondly, a conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is embedded into the electrospun fibres by oxidative chemical polymerization of EDOT-swollen microfiber mats. This two-step process affords robust, highly flexible and conductive s-IPN microfiber mats. The microfiber mat undergoes a controllable pore size variation upon applying an electrochemical stimulus in the form of a reduction-oxidation cycle to the mats in an electrolyte. The maximum average pore size variation, measured in situ using confocal microscopy, is 25%, achieved in 1 M lithium bistrifluoromethanesulfonimide (LiTFSI) in propylene carbonate (PC) for a potential step between +0.6 V and À0.5 V (vs. Ag wire). These mats also show pore size variation in a biologically compatible solution, phosphate buffered saline. † Electronic supplementary information (ESI) available: Video showing pore size variation in 1 M LiTFSI PC solution, properties and compositions of nonelectrospun films, SEM and EDX of electrospun microfibers and PEDOT embedded fibres respectively, and confocal microscopy and pore size variation data for microfiber mats in PBS solution. See
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.