Preparation and Characterization of Electrospun Conductive Janus Nanofibers with Polyaniline

Multifunctional composite fibers have important applications in various fields. Different components in the composite can be combined to form a fiber in various configurations, with homogeneous blending being the most commonly used configuration. Fibers of heterogeneous configurations with a layered structure are unique in that their multifunctionalities are manifested through maintaining the distinct properties of each component. The interaction between components is limited at their 2D interface. In this study, using a Y-shape spinneret, electrospun side-by-side nanofibers were prepared that contained conductive camphoric acid doped polyaniline (PANI-CSA) blended with either nonconductive poly(ethylene oxide) (PEO) or polyvinylpyrrolidone (PVP) as one side and PEO or PVP as the other side. Nanofiber morphology and various fiber mat properties were systematically evaluated. The influence of fiber morphology, configuration, and side-by-side fiber interface on fiber mat properties was analyzed. Results indicated that sufficient contacting time and area of the two solutions before being ejected into fibers during electrospinning were critical for creating the side-by-side configuration. When the matrix polymers on the two sides were the same, the side-by-side fibers possessed improved mechanical properties than single blended fibers and similar electrical conductivity, although no visible boundary between the layers was observed. When the matrix polymers were different, a visible boundary existed between the two sides. The side-by-side fiber exhibited integrated mechanical performance combining that of the two sides, indicating that there was enough interfacial bonding between the two sides.