Octadecylphosphonic acid is used as detergents, dispersants, emulsifiers, and chelating agents. Alkyl phosphonic acids are typically sparingly soluble in both organic solvents and water, but become more soluble in water when neutralized to phosphonates at neutral to high pH.
n-Octadecylphosphonic acid is used in thermal paper for receipts, adding machines and tickets. It acts as surfactant, emulsifier, dispersants and chelating agents. Further, it is a long chain phosphonic acid compound utilized for proteomics research. In addition to this, it is used to prepare modified mesoporous magnetic nano particles through Lewis acid/base interaction.
Octadecylphosphonic acid (OPA) is used as a self-assembled monolayer that forms a surfactant which strongly bonds with the surface atoms of different metal oxides. It provides hydrophobic properties and covers a higher surface area than the predominantly used silanes.