A scalable synthesis of copper nanowires by alternating current electrodeposition into porous aluminium oxide was used to produce multigram quantities of 16 nm diameter by >2 mu m long nanowires. Polystyrene nanocomposites were prepared by solution processing. The composites containing unpassivated nanowires were non-uniformly dispersed and showed electrical percolation at approximate to 2 vol.-% Cu loading, while the composites containing HSC18H37-passivated nanowires were uniformly dispersed, but remained resistive up to at least 10 vol.-% Cu loading.