Magnetic field mediated nanowire alignment in liquids for nanocomposite synthesis

The motion of magnetic nanowires can be manipulated by a magnetic field in liquids so that their distribution, alignment and orientation can be effectively controlled. The small dimensions of nanoscale entities result in an extremely low Reynolds number, and a steady state Stokes flow approximation was adopted to analyze the nanowire motion under the influences of applied field. The effects of fluid viscosity and external field on the motion of different sized nanowires were investigated. Polydimethylsiloxane composites with nickel nanowires as reinforcing fillers were synthesized as a demonstration of the effectiveness of magnetic alignment. Anisotropic magnetic properties and mechanical strengthening effects were explored.