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Flash pyrolysis of polyethyleneglycol by T-Jump/FTIR spectroscopy to temperatures of the surface during combustion reveals that volatile products arise from approximately equal amounts of C-O and C-C homolysis. Nine volatile products are discussed. The average number of repeating units in the volatile oligomers is 2.5. A shift in product distribution occurs at 420–480°C resulting from a change in the polymer structure. Below 420°C, di- and mono-ether oligomers and diethyleneglycol dominate. Above 480°C, the mono-ethers and ethyleneglycol dominate. The Arrhenius constants for decomposition reflect this difference: Ea=8.8 kcal mol−1, In (A, s−1) =2.0 at 370–420°C and Ea=19 kcal mol−1, In (A, s−1)=10 at 480–550°C.

The principal binder of many LOVA propellants is cellulose acetate butyrate (CAB). By the use of T-Jump/FTIR spectroscopy, CAB was flash-pyrolyzed to set temperatures in the 465–600°C range, while rapid-scan IR spectra were used to identify the main decomposition products and to measure the rate of formation of each product as a function of temperature. Eleven specific products, which include oligomers of CAB, acids, aldehydes, ketenes, esters, CO2 and CO, were quantified by chemometric procedures. The ketenes are the most novel products. The Arrhenius parameters reveal that below 510 ± 20°C, the rate of product evolution is controlled mainly by condensed phase reactions. Above 510 ± 20°C, the rate of product evolution is controlled by desorption/evaporation of the volatile products.