The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurement...The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurements. The effects of various environmental and corrosive factors on the paints were also studied. The study showed that the alkyd paint samples formulated using the core-shell pigments generally had low specific gravity (1.30 – 1.38), an indication that more of the core-shell pigments can be incorporated into the alkyd paints with considerable cost savings. The dry film thicknesses of the paint samples falls within 0.24 - 0.39 mm, suggesting that the samples will perform well as anticorrosive coatings and their adhesion properties are generally good, showing that they can withstand abrasive and corrosive agents. The core-shell extender pigments formulated paint samples were observed to exhibit the best dust-free, tack-free, and through dry times compared to TiO<sub>2</sub> paint formulation. The formulated paint samples generally performed well on exposure to rain and sunlight as well as in distilled water, 2% Na<sub>2</sub>CO<sub>3</sub>, and 2% H<sub>2</sub>SO<sub>4</sub> with only TiO<sub>2</sub> paint formulation exhibiting rust. The good paint performance characteristics obtainable with the core-shell extender pigments are enough evidence to justify their utilization in the surface coatings industry. The performances of these core-shell extender pigments in alkyd paints have shown that they combine the properties of both the clays and titanium dioxide, and have the potential to overcome their disadvantages.展开更多
The extender properties of some Nigeria clays have been studied. The local clays were characterized using X-ray fluorescence and scanning electron microscope. The physico-chemical properties of the clays were evaluate...The extender properties of some Nigeria clays have been studied. The local clays were characterized using X-ray fluorescence and scanning electron microscope. The physico-chemical properties of the clays were evaluated using ASTM standards. The physico-chemical characterization of the local clays gave the following results: specific gravity (2.54 and 2.49), oil absorption (51.0 and 59.0 g/100g), refractive index (1.7 and 2.0) and pH (5.1 and 4.8) for Nsu and Ihitte-Uboma clays respectively. Compositional analysis showed that the clays consisted predominantly of silica (SiO2) and aluminium oxide (Al2O3) in high proportions with the other constituents present in very small proportions. The clays were stable to heat and insoluble in toluene, methanol, ethanol, 2-propanol, chloroform and hydrochloric acidexcept for their slight solubility in acetic acid. The colour of the clays was not affected in cold or when heated except for slight colour change observed in the presence of hydrochloric acid when heated. The particle morphology of the clays indicated the presence of sub-angular platelet of varying sizes. The optimum calcination temperature of the clays was determined to be 850°C for use in oil-based paints. The clays can be used in gloss paints, rubber and plastic composites and as an adsorbent with improved properties.展开更多
文摘The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurements. The effects of various environmental and corrosive factors on the paints were also studied. The study showed that the alkyd paint samples formulated using the core-shell pigments generally had low specific gravity (1.30 – 1.38), an indication that more of the core-shell pigments can be incorporated into the alkyd paints with considerable cost savings. The dry film thicknesses of the paint samples falls within 0.24 - 0.39 mm, suggesting that the samples will perform well as anticorrosive coatings and their adhesion properties are generally good, showing that they can withstand abrasive and corrosive agents. The core-shell extender pigments formulated paint samples were observed to exhibit the best dust-free, tack-free, and through dry times compared to TiO<sub>2</sub> paint formulation. The formulated paint samples generally performed well on exposure to rain and sunlight as well as in distilled water, 2% Na<sub>2</sub>CO<sub>3</sub>, and 2% H<sub>2</sub>SO<sub>4</sub> with only TiO<sub>2</sub> paint formulation exhibiting rust. The good paint performance characteristics obtainable with the core-shell extender pigments are enough evidence to justify their utilization in the surface coatings industry. The performances of these core-shell extender pigments in alkyd paints have shown that they combine the properties of both the clays and titanium dioxide, and have the potential to overcome their disadvantages.
文摘The extender properties of some Nigeria clays have been studied. The local clays were characterized using X-ray fluorescence and scanning electron microscope. The physico-chemical properties of the clays were evaluated using ASTM standards. The physico-chemical characterization of the local clays gave the following results: specific gravity (2.54 and 2.49), oil absorption (51.0 and 59.0 g/100g), refractive index (1.7 and 2.0) and pH (5.1 and 4.8) for Nsu and Ihitte-Uboma clays respectively. Compositional analysis showed that the clays consisted predominantly of silica (SiO2) and aluminium oxide (Al2O3) in high proportions with the other constituents present in very small proportions. The clays were stable to heat and insoluble in toluene, methanol, ethanol, 2-propanol, chloroform and hydrochloric acidexcept for their slight solubility in acetic acid. The colour of the clays was not affected in cold or when heated except for slight colour change observed in the presence of hydrochloric acid when heated. The particle morphology of the clays indicated the presence of sub-angular platelet of varying sizes. The optimum calcination temperature of the clays was determined to be 850°C for use in oil-based paints. The clays can be used in gloss paints, rubber and plastic composites and as an adsorbent with improved properties.
