Direct measurement of multiwall nanotube surface tension

The contact angle between multiwall carbon nanotubes, carbon nanofiber and carbon fibers, and polypropylene and polyethylene glycol was measured using electron microscopy. Good wetting was observed using both polymers. The Owens–Wendt plotting procedure was used to obtain the polar, dispersive and total surface energy parameters for the three types of carbon materials. Minor differences only were found between these.