炭黑的pH值与氧含量、表面酸性含氧基团含量的规律性

Relationship Between pH and Contents of Oxygen and Surface Oxygenous Acid Group of Carbon Black

炭黑的表面性质对其应用有重要影响.本文研究了炭黑的元素组成、pH值、表面酸性含氧基团含量以及它们之间的相互关系.实验结果表明,炭黑的pH值取决于其氧含量,两者存在指数关系.详细讨论了测定条件对炭黑表面酸性含氧基团测定结果的影响.实验结果表明,中和反应时间为90min、碱溶液浓度为0.05mol/L时,实验的重复性较好.同时测定了炭黑表面羧基、酚羟基、内酯基等酸性含氧基团的含量.实验结果表明,炭黑的pH值与其表面酸性基团含量存在指数关联.

The surface properties of carbon black affect its application remarkably. The element composition, pH value, contents of acid oxygenous groups of carbon black, and their internal relationships have been studied. It is found that the oxygen content is correlated with pH value of carbon black, and their correlation can be described by the exponential function nearly. The effect of testing conditions on test results of acid oxygenous groups on carbon black has been studied detailedly. The repeatability of test results is good under given conditions that the time of neutralization reaction is 90 min and the base concentration is 0.05 mol/L.The contents of carboxyl, phenol hydroxyl, and lactones groups on carbon black surface have been determined. The results of experimentation indicate exponential relationship between pH value of carbon black and contents of acidic groups on carbon black surface.