Dispersion of copper phthalocyanine pigment nanoparticles by eco-friendly ethoxylated cardanol in aqueous solution

Abstract The environmentally friendly surfactant ethoxylated cardanol (EC) was investigated for dispersing copper phthalocyanine (CuPc) pigment nanoparticles into aqueous solution. The stability of the dispersion was investigated using UV-Vis spectra. The particle size was measured by optical microscopy, transmission electron microscopy and dynamic light scattering. The surface of the nanoparticles was characterised by measurements of the zeta potential and wettability. The coating application was investigated by incorporating CuPc blue pigment into resin and inorganic filler, and the colour strength of the coating film was compared. The results show that the EC can effectively wet and disperse the CuPc particles. The stabilisation of the particles is achieved by a steric mechanism in which the hydrophobic chains of the surfactant are adsorbed onto the surfaces of the CuPc nanoparticles and the ethylene oxide chains are dispersed in the aqueous phase. At EC concentrations greater than 0.1%, the CuPc nanoparticles appear to deagglomerate. The colour strength of CuPc nanoparticles present as dispersed pigment in resin can be increased in the presence of the EC surfactant.