The Surface Chemistry and Solution Behavior of Dinonylnaphthalene Sulfonic Acid - Recent Advances

Abstract

Soon after its initial preparation 30 years ago, dinonylnaphthalene sulfonic acid attracted considerable attention from surface chemists as an early example of a uniform synthetic high-molecular-weight sulfonic acid. Early work focused on the inverted micelles formed by DNNSA and its salts in nonpolar solvents, and it was soon found that certain salts of the acid are effective oil-soluble corrosion inhibitors. DNNSA has been employed in many published studies to determine the stability constants of inorganic complexes in solution. As early as 1957 it was discovered that DNNSA solutions in nonpolar organic solvents will extract metallic ions from aqueous solutions across the aqueous-organic interface. This was the first of many studies of the acid as a liquid ion exchange reagent. In related developments it has been found that DNNSA is an effective phase-transfer catalyst. Not surprisingly, the acid has been found to be an effective acid catalyst in promoting reactions in organic media. Very recent work has further pursued the nature of DNNSA inverted micelles, particularly the factors affecting water and mineral acid inclusion in the micelles, water displacement from the micelles by weak organic acids, and mixed micelles.