Decomposition of diphenylamine in nitrocellulose based propellants-II. Application of a numerical model to concentration-time data determined by liquid chromatography and dual-wavelength detection.
A continued investigation of the primary steps in diphenylamine (DPA) decomposition in nitrocellulose (NC) propellants is presented. The study is based on analytical data obtained by reversed-phase liquid chromatographic separation of the initial degradation products of DPA. Spectrophotometric detection, rather than the amperometric detection used in part I of this work (A. Bergens and R. Danielsson, Talanta, 1995, 42, 171), was employed in order to detect N-nitroso-DPA as well as DPA, 2-nitro-DPA and 4-nitro-DPA. The results have been studied with the rate parameter optimization program described in part I and simulations suggest that the decomposition of DPA includes unknown reaction steps. More satisfying curve fits were, for example, obtained when the initial reaction for conversion of DPA into N-nitroso-DPA was considered to consist of a two step process with an intermediate. This intermediate could act as a stabilizer as well as DPA and N-nitroso-DPA, particularly at lower temperatures.
Bergens
A
A
Uppsala University, Institute of Chemistry, Department of Analytical Chemistry, P.O. Box 531, S-751 21 Uppsala, Sweden.