화학공학소재연구정보센터
Propellants Explosives Pyrotechnics, Vol.45, No.7, 1088-1101, 2020
A New Procedure for Stability Control of Homogeneous Solid Propellants by Combination of Vacuum Stability Test, FTIR and PCA
Stability control and evaluation for Homogeneous Solid Propellant (HSP) are of paramount importance for securing ammunition storage warehouses and weapon systems. In the current work, a new procedure for the stability control of HSP was established by combining spectral, thermal, and chemometric tools. Analyses were performed on three similar HSPs naturally aged up to 31 years and subjected to artificial aging (during 12 months at 338.65 K with sampling every 2 months). FTIR analysis showed a decrease in the intensities of the characteristic bands with natural/artificial aging progress. Vacuum Stability Test (VST) experiments carried out at five isothermal temperatures (333.15 K, 343.15 K, 353.15 K, 363.15 K, and 373.15 K) highlighted three degradation stages during HSP aging. Two kinetic approaches, viz, model-fitting and model-free have been applied to VST data in order to evaluate the kinetic parameters. The activation energy for the HSP degradation reaction was found to decrease with natural/artificial aging progress. Furthermore, the application of the Principal Component Analysis (PCA) to FTIR spectra allows classifying efficiently the samples according to their stability properties. Moreover, the loading plots pointed out the most influenced bands by aging processes. A model, which connected the mean intensity of these bands to the activation energy of the sample, was established. Furthermore, the limit of propellant stability was estimated based on the prediction of the storage lifetimes. The relative error on the activation energy associated with the obtained model was found to be less than 2 % during natural aging up to 20 years and 6 % during artificial aging up to 12 months.