N,N-Di-n-octylaniline is a chemical compound that is used as an additive in the production of polycarboxylic acids. It is also used as a monomer in the production of ester compounds. The hydroxy group on this molecule can be converted to an amide or sulfonamide group, which gives it its anti-aging properties. N,N-Di-n-octylaniline has been shown to increase membrane potential and viscosity, while decreasing acid catalyst and additives. This compound contains a metal cation that can be removed by adding an acid.