Electrospun Polymer Nanofiber Scaffolds for Functionalized Long Sub-Micron Diameter Cables

Abstract

Utilization of thin, flexible, and conductive wires that are twisted in a bundle has significantly improved the performance of communication devices operating at MHz frequencies. For GHz frequency applications, available wires are too large in diameter, and development of new synthetic methodologies are required to shrink such wires to sub-micron scale while retaining their mechanical strength, along with electrical conductivity and insulation from neighboring wires. We present a new method for the preparation of strong, flexible and centimeter-long insulated nanocables on a high-strength polymer nanofiber scaffold. Single strands of poly(m-phenylene isophthalamide) nanofibers with diameters in the range of 300 - 600 nm were prepared via electrospinning onto a rotating collector. Coaxial coatings of a variety of metals and insulators were performed to illustrate the materials generality of the methodology. The flexibility and compatibility with extreme deposition conditions (up to 350 °C) offered by this nanofiber scaffold paves the way for the improvement of communication devices in the GHz range.