Study On Technologies Of Characterization And Grafting Polymers For Carbon Black Pigment

The carbon black pigment is applied to the fields of presswork, coating, and plastic industry. The study on its characterization technology is necessary condition and base of study and development for high-level carbon black pigment. In this paper, the characterization technology has been studied, and the properties of element composition, pH value, surface acid, granularity, specific surface area from carbon black have been researched.1 The pH value of carbon black is important parameter of estimating oxidation degree of carbon black. The oxide content and surface acidic groups determine the surface chemical property of carbon black. The acidic oxygenous groups as carboxyl group, phenolic hydroxyl group, and lactone group on surface of carbon black samples from inland and oversea have been distinguished, and their contents nave been mensurated by means of acidic and bases titration. the element compositions of the carbon black samples have been mensurated by means of element analysis method. The experiment results show that the relationships between pH and contents of oxide, total acid and carboxyl group are obvious and inevitable.2The method of IR for distinguishing surface chemical groups of carbon black is very difficult because the contents of surface acidic groups is low, and the adsorption to infrared ray of carbon black is intensive. The element composition and chemical structures on carbon black surface are studied efficiently by means of XPS. The experiment results show that the content of C=O on surface of connect black is higher than of furnace black, and ozone oxidation progress increases the content of C-O on surface of furnace carbon black, and farther oxidation of furnace black surface is difficult.3 The granularity distributing of carbon black aggregate is logarithmic normal school. The figure of granularity distributing of carbon black particles in water could be analyzed by this conception. The particles of connect black dispersed in water are aggregate structure basically because the contents of acidic oxygenous groups is plenty. The mean granularity of furnace black particle dispersed in water is higher than of connect black because the trend that the particles of furnace black are attached each other is strong. The dispersion stability of carbon black in solvents is bad for litter particle size, high surface energy, and trend of aggregating each other. Using technology of grafting polymers onto surface of carbon black can improve the dispersion stability of carbon black particles in solvents. The poly-glycol had been selected as grafted polymer oncarbon black . Connect black and furnace black had been selected basic carbon black .The carbon black grafting polymers had been made by means of surface combination reaction in this work. The effect of reaction conditions on grafting percent and molecular weight of grafted polymers on dispersibility and dispersion stability had been studied. 4Carbon black will be activated if the surface carboxyl group is converted to acyl chloride group. The activities of carboxyl group on connect black and furnace black is different. The grafting mass percent of connect black is more than of furnace black because of difference in carboxyl group content. One poly-glycol molecule react with one acyl chloride group on carbon black surface, and molecular weight of polymer affect grafting mole percent.5The poly-glycol grafted on carbon black decreases the size of carbon black particles dispersed in water. The molecular weight of grafted polymer affect dispersion of carbon black. The experiment result show that higher molecular weight is favorable for carbon black dispersion. The furnace black drafting poly-glycol can improve dispersion stability of carbon black in water and 2-propyl alcohol, and the effect is determined also by the molecular weight. 6The poly-glycol grafted on carbon black does not decrease the size of connect black particles dispersed in water. The dispersion stability of connect black grafting poly-glycol in wat...