Preparation and characterisation of water-based aluminium pigments modified with SiO2 and polymer brushes

In order to improve the corrosion resistance and dispersiveness of aluminium pigments in aqueous media, SiO 2 -coated aluminium was prepared and polyacrylic acid brushes were grafted on its surface. A decrease in hydrogen generation indicated that the corrosion resistance was improved by the SiO 2 coating, while the polyacrylic acid brushes improved dispersiveness. The d (0.5) (particle size of 50% volume fraction) values of the SiO 2 -coated aluminium sample and that of the sample with the polyacrylic acid brushes grafted on it were 41   μm and 29   μm, respectively. We believe that thus modified aluminium will find use in water-based paints and printing inks.