Highly Stretchable and Permeable Conductors Based on Shrinkable Electrospun Fiber Mats

Wearable on-skin electrodes or conductors should be vapor permeable, strain-insensitive, isotropically stretchable and stable under cyclic stretching. Various strategies have been proposed to prepare the required conductors up to now; however, it is a challenge to fabricate them with above properties in a simple manner. In this paper, a highly permeable and stretchable conductor based on electrospun fluorine rubber fiber mat is reported. The fibers are pre-stretched in electric field during electrospinning, and they shrink isotropically by ~ 35–40% in area after being detached from the substrate. The obtained fiber mat conductor demonstrates high stretchability up to ~ 170%, and the resistance changes only 0.8 under 60% strain, which is superior to many other strain-insensitive conductors. The conductor possesses high stability, no cracks or structure damage are observed after washing and cyclic stretching. Moreover, the conductor is vapor permeable with a water vapor transmission rate of ~ 850 g m−2 day−1, which is comparable to the normal water evaporation in ambient conditions, indicating that it would not disturb the sweat evaporation when being used on skin. The conductor is successfully used as stretchable yarns and electromyography (EMG) electrodes, showing high reliability in E-textiles and on-skin applications.