QUANTITATIVE-DETERMINATION OF STABILIZER IN A SINGLE-BASE PROPELLANT BY CHEMOMETRIC ANALYSIS OF FOURIER-TRANSFORM INFRARED-SPECTRA

The main constituent in a propellant is nitrocellulose, which by natur e is unstable, and consequently it has to be stabilised with, e.g., di phenylamine. In order to determine the remaining shelflife of the prop ellant, the amount of stabiliser is determined. The method mostly used for this purpose, high-performance liquid chromatography (HPLC), is h owever complex and time consuming. Partial least squares calibration o f the infrared spectroscopic profiles of the stabiliser and its deriva tives in the propellant against their respective quantities (determine d by HPLC) was tested to find out whether the quantitative determinati on of the above was possible. The initial results show that the cross- validated calibration model yields quantitative determination of the s tabiliser and its derivatives within an error limit of 10% in predicte d values. The correlation between the measured and predicted values wa s better than 0.94 for the stabiliser and its three first derivatives.