| Summary: | Chemical stabilisers are incorporated into nitrate ester based propellant formulations to react with the initial propellant decomposition products, preventing the onset of autocatalytic deterioration of these energetic constituents. As a result of these interactions the stabiliser forms a number of derivatives. Sources of these propellant stabiliser degradation products are vital for investigating the course of propellant breakdown and for the validation of several established stability tests. Synthetic methodologies have been developed which yield targeted derivatives of diphenylamine via catalysed and uncatalysed nucleophilic aromatic substitutions in conjunction with standard nitrosating techniques. Ethylcentralite, used in double or triple base propellants, reacts depending on stabiliser concentration, to give two distinct groups of degradation products. Those based on the N-ethylaniline nucleus and those based on the parent stabiliser. The derivatives based on N-ethylaniline have been synthesised utilising a variety of synthetic approaches including phase transfer catalysed N-alkylation, while the utility of urea synthesis employing the reaction between anilines and isocyanates has been evaluated as a possible route towards the second group of ethylcentralite propellant stabiliser degradation products. High performance liquid chromatographic techniques have been developed for the quantitative assay of the diphenylamine and ethylcentralite stabiliser derivatives synthesised. Preliminary analysis of different single base propellants, stabilised by diphenylamine, indicate markedly different degrative product profiles for each of the samples studiedFinally an investigation of a resorcinol stabilised model propellant system has provided evidence that 2-nitroresorcinol, 4-nitroresorcinol and lacmosol are propellant stabiliser degradation products of the aforementioned stabiliser
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