Incorporating Strong Polarity Minerals of Tourmaline with Carbon Nanotubes to Improve the Electrical and Electromagnetic Interference Shielding Properties

This paper describes a method for enhancing the electron transition among carbon nanotubes (CNTs) by integrating CNTs with a polar mineral tourmaline having spontaneous electric fields for conductive polymer composites. The thin polymer layer at the surfaces of CNTs raises the potential barrier of electron transition among CNTs, limiting the electrical properties. The incorporation of tourmaline particles (TPs) enhanced significantly the electrical properties of polyurethane/multiwalled carbon nanotube (PU/MWNT) composites. The electric fields of TPs lower the potential barrier by an applied external electric field. It is proposed that the enhanced electrical properties are due to a reduction in the potential barrier of electron hopping among CNTs. The results have important implications for enhancing the electrical properties of conductive polymer composites, endowing the composites with new fuctions, such as nagetive air ions and far-infrared emission.