Mechanism of Pyrolysis Reaction of Al-Rich Al/PTFE/TiH Active Material.

In order to obtain the chemical reaction mechanism of Al-rich Al/PTFE/TiH composites in argon and oxygen atmosphere, Al/PTFE, PTFE/TiH, Al/TiH and Al-rich Al/PTFE/TiH with different contents of TiH composites were prepared by using the wet mixing method. The pyrolysis behavior of the above composites was investigated by thermogravimetric differential scanning calorimeter (TG-DSC). In addition, the calorific value of the above composite was measured by an oxygen bomb calorimeter. The compositions of TG-DSC residues at different peak temperatures and 1000 °C and the residues of oxygen bomb experiment were analyzed by X-ray diffraction (XRD), The results show that the pyrolytic products of Al-rich Al/PTFE/TiH materials under argon atmosphere can be divided into four stages. In the first stage (328.6-378.6 °C), the products are TiH, (CF), (CF), H(g), Al and TiH; in the second stage (510.8-534.3 °C), the products are Al, TiH, (CF), (CF), Ti, AlF, TiF, TiF(g), C and H(g). In the third stage (540.8-618.1 °C), the products are Al, C, Ti, (CF), (CF), AlF, TiF, TiF, CF(g), CF(g), CF(g), CF(g), AlTi and H(g); in the fourth stage (918.5-1000 °C), the products are AlCTi, AlTi, AlTi, TiC, AlF, Al, TiF, TiC, TiC and TiC. The calorific value of the combustion of Al-rich Al/PTFE/TiH composite with 10% the content of TiH is the highest and is 19,899 J/g, which is 3.776% higher than that of Al-rich Al/PTFE composite. When TiH content is greater than zero and not more than 10%, the chemical reaction mechanism of Al-rich Al/PTFE/TiH is almost the same under oxygen atmosphere. When the content of TiH is higher than 10%, the mechanism of this material is different.