Laser ignition and combustion properties of composite with high-substituted nitrochitosan and nano-Ti powder

Abstract

Although nano-Ti powder (n-Ti) exhibits a good application prospect in energetic materials, its agglomeration would weak the combustion efficiency and hinder its application as a combustion additive in solid propellants. Herein, the homogeneous binary composite nitrochitosan/nano-Ti (NCh/n-Ti) was prepared in acetone. The morphology structure, thermal behavior, laser ignition and impact sensitivity of NCh/n-Ti and nitrocellulose/nano-Ti (NC/n-Ti) were contrastively researched. The thermal decomposition temperature of NCh/n-Ti is lower than that of NC/n-Ti for the decomposition character of NCh, but NCh/n-Ti composites with the mass ratio of 1:3, 1:5 and 1:7 all exhibit higher flame propagation speed (48.5, 66.0 and 20.9 m s−1) than that of corresponding NC/n-Ti composites at the laser energy density of 130.7 W cm−2. And the ignition delay times for NCh/n-Ti composites are 8.5 (1:3), 5.3 (1:5) and 3.4 ms (1:7) respectively, which are all lower than that of the corresponding NC/n-Ti composites. Furthermore, the impact sensitivity of NCh/n-Ti is lower than that of corresponding NC/n-Ti. NCh/n-Ti presents better performances than NC/n-Ti. NCh can provide a new insight for high-energy dispersion medium instead of NC.