Thermal Decomposition of Enegy Composite Material with an Inert Binder

Resumo

Results are presented of a study into the kinetics of thermal decomposition of a vulcanized mixed energy formulation K-2, the main components of which are ammonium perchlorate, octogene, aluminum, and inert binder, macromolecular cis-polybutadiene plasticized with transformer oil. In experiments with open crucibles, evaporation of the plasticizer, thermal decomposition of octogene and ammonium perchlorate successively occur in the samples. The dependence of the activation energy E on the conversion α is complicated: its minimum value (65 kJ mol⁻¹) corresponds to the evaporation of the plasticizer, and the maximum value (192 kJ mol⁻¹ at α ≈ 0.27), to the decomposition of octogene. At any hindrance to the free egress of decomposition products (packing of samples in an aluminum foil or the hermetical sealing), reactions occur in a “self-generated” atmosphere, and the type of K-2 decomposition changes. For samples in the foil, the exothermic peak of octogene is shifted to higher temperatures, the maximum of the activation energy (182 kJ mol⁻¹) corresponds to α ≈ 0.45, and the loss of mass by K-2 samples is complete at lower temperatures. Reasons for this transformation of the K-2 decomposition pattern are discussed.