THERMAL-DECOMPOSITION OF ENERGETIC MATERIALS .51. KINETICS OF WEIGHT-LOSS FROM NITRATE ESTER POLYMERS AT LOW HEATING RATES

The kinetics of weight loss of six polymeric nitrate esters is described by the non-linear least-squares fit of non-isothermal TGA weight-loss curves. In the first 50% of weight loss, nitrocellulose (9.45%, 11.7%, and 13.4% nitrogen) and poly(vinyl nitrate) undergo first-order autocatalytic decomposition. Poly(glycidyl nitrate) and poly(nitratomethylmethyloxethane) exhibit simple first-order kinetics. The tendency to become autocatalytic follows the trend toward higher oxygen balance, higher viscosity, and the increased presence of secondary alkyl nitrate sites in the molecules.