Spectrofluorimetric determination of phenyl-beta-naphthylamine used as rubber antioxidant.

Phenyl-beta-naphthylamine (PBN) used as rubber antioxidant was found to have native fluorescence. A spectrofluorimetric method for determination of PBN in multicomponent mixtures of polymer additives is described. The apparent excitation and fluorescence wavelengths used are 348 and 413.5 nm, respectively. Maximum fluorescence intensity is obtained by irradiating PBN dissolved in ethanol, at room temperature. The fluorescence varies linearly with the concentration of PBN in the range of 0.04-4 microg mL(-1). The accuracy and precision of the method are reported.