Carbon nanotube/polyurethane films with high transparency, low sheet resistance and strong adhesion for antistatic application

Antistatic technology has been applied in all aspects of modern life, including the manufacture of electronic products, aerospace systems, daily necessities and so on. The main purpose of this study is to obtain, using the Mayer rod-coating method, a flexible antistatic film with high transmittance, low sheet resistance and strong adhesion. With the help of the dispersant, single-walled carbon nanotubes (SWCNTs) were dispersed in water to form an homogeneous dispersion. The SWCNT dispersion was coated onto a poly(ethylene terephthalate) (PET) film with use of a rod to produce a uniform film. The antistatic films obtained had special characteristics, such as high transparency, low sheet resistance and excellent resistance to water and heat. Sheet resistance varied between 102–105 Ω sq−1 by controlling the content of water-based polyurethane (WPU), changing the thickness of the films and the post-treatment. The best film had a sheet resistance of 423 Ω sq−1 with 82.7% transmittance. In particular, the addition of the WPU binder greatly improved the adhesion between the CNTs and the PET film. Scanning electron microscopy, energy dispersive X-ray spectroscopy and Scotch™ tape method were conducted to determine the microstructure, cleanliness, and adhesion of the film, respectively.