The Research Of Graphene/polyurethane Conductive Coatings

Polyurethane has been widely used in plastics, coatings, adhesives, and other fields, which has strong adsorption capacity, strong acid and alkali, wear resistance and other advantages. It can not be used as conductive materials, because it is a insulation material. The addition of nano conductive filler can enhance the electrical conductivity, glass transition temperature, energy storage modulus of the composite. Then it can be used in aviation, oil and gas storage and transportation, etc. In this paper, graphene was used to be the nano conductive filler to modify polyurethane and the polyurethane conductive coating has excellent properties. The preparation of graphene and the polyurethane conductive coating, the dispersion of graphene was discussed in the article.This article has explored that graphfite oxide is prepared by improved Hummers oxidation. It has analyzed the graphite oxide structure which is influenced by the raw material, catalyst dosage, the oxidation time, intercalating agent, and the graphene structure which is influenced by reduction agents and dosage, the time. The graphite oxide and graphene were characterized by infrared spectroscopy(FTIR), X-ray diffraction(XRD), transmission electron microscope(TEM). We choose the best preparation technology of grapheme, as follow: The stable dispersions of Graphene is prepared by improved Hummers oxidation, expanded graphite as raw material, mixture of H2SO4, P2O5, and Na NO3 as intercalating agent, potassium permanganate and hydrogen peroxide as an oxidant, oxidation 5h, ultrasonic 0.5h, hydrazine hydrate restore 8h.Reference to the study on the dispersion of carbon nanotubes, the effect of the polarity of the solvent, viscosity, the type and amount of dispersant, ultrasonic time on Graphene dispersion were explored. The graphene dispersion stability is characterized by the Fluorescent electronic microscope and the Zeta potential. The dispersion is stability when we elected ethanol amine as dispersion, anionic as initiator, ultrasonic 6 h, configuring 0.2mg/m L.The suitable polyurethane matrix was choosed to mix with graphene dispersion to explore the dispersibility in polyurethane emulsion. The influence of the graphene content on electrical conductivity, the glass transition temperature the storage modulus were discussed. The conductivity of matrix mixed is enhanced not too much by solution-mixing, but spin graphene on the surface can significantly improved the electrical conductivity.