Preparation and physicochemical properties of graphene ink for 3D inkjet printing

Abstract Based on the advantages of Graphene(Gr), such as low cost, high conductivity, low oxidation resistance and high chemical stability, Gr ink is prepared: Gr dispersion was prepared in isopropyl alcohol and water by adding polyvinylpyrrolidone (PVP) and sodium dodecyl sulfonate (SDS).By studying the stability of Gr dispersions, the optimal dispersants and proportions were further screened, and different concentrations of Gr inks were prepared on the basis of the optimal dispersants and proportions. The particle size, viscosity, surface tension, density, pH, conductivity and other physical and chemical properties of Gr ink were tested. The experimental results showed that (1) The dispersion effect of PVP was better than that of SDS. With the increase of PVP ratio, the stability time of the dispersion solution first increased and then stabilized, and the optimal dispersion ratio was obtained as W Gr : W PVP = 2:1. (2) The concentration of Gr is positively correlated with the physical and chemical properties such as density, viscosity and particle size. With the increase of graphene concentration, the density, viscosity and particle size all increase. The surface tension is greatly affected by solvent properties. (3) After calculation and comparison of ink rheological properties, isopropyl alcohol (IPA) as solvent group, Gr 35 mg/mL and 50 mg/mL, meet the requirements of commercial printing; IPA-H 2 O was the solvent group. Except for the Gr concentration of 50 mg/mL, serious shear conversion behavior appeared. The Gr inks with other concentrations had good compatibility with the nozzle, which was suitable for inkjet 3D printing technology.