Evaluating the Extender Characteristics of Some Local Materials in Akure, Ondo State, Nigeria for Applications in the Paints Industry

Abstract

Soil samples were obtained from three different locations; Ijapo, Ibule and FUTA North Gate in Akure, Ondo State, Nigeria. The materials were dried, crushed and calcined by heating the samples in a muffle furnace to 850 °C, holding for three hours and and then brought out of the furnace to cool in the laboratory so that the organic and volatile matter escaped, and the oxide content increased. The calcined materials were milled with a ball mill and then sieved with 75 µm mesh size British standard sieves. The samples that passed through the sieves were collected for analysis to determine their extender characteristics through x-ray flouresence (XRF) spectroscopy, x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), specific gravity, oil absorption, pH and refractive index measurements as well as the determination of their resistance to chemicals. XRF results showed that materials are kaolinite in nature. XRD results showed the phase compositions of each sample as materials suitable for applications as extenders in the paints industry. SEM micrographs showed the homogeneity of the samples from Ijapo and FUTA North Gate while the sample from Ibule showed segregation of the phase compositions. The specific gravity, pH, oil absorption and refractive index of each material were within the range of those of commercial extenders used in the paints industry. The calcined materials were found to be resistant to various chemical media. The characterized materials will be suitable as extenders and pigments in the paints industry.