Preparation Of Microporous Ball Flat Medicine And Its Application

Becsuse of the flowing property good, production process simple and safe,the oblate spherical propellants have been the main propulsion energy of light weapons, especially small arms. In this paper, the microfoam oblate spherical propellants with the "skin-core" structure were prepared successfully by supercritical CO2foaming technology by controlling the process conditions, the effects of processing parameters such as CO2dissolved quantity, desorption time and foaming temperature on the foam morphology of microfoam oblate spherical propellants were investigated by scanning electron microscope (SEM).Then, a kind of whole grain with high burning rate was prepared by using the oblate spherical propellants as materials. In additions, the burning performances and mechanical properties of the whole grain were studied.The results indicated that the internal foam morphology and the thickness of the shell could be changed by adjusting the foaming parameter, when the CO2dissolved quantity increased from11.880%to13.429%, the foam diameter increased from4.32um to4.93um,the thickness of the shell decreased from17.45um to10.50um,while the foam density showed a little change. Under the condition of the foaming temperature of100℃, when the desorption time was varied from1min to20min,the foam density descreased from1.16×109cells·cm-3to0.4×108cells·cm-3, while the foam diameter varied little.The whole grain was prepared by using the oblate spherical propellants as materials,nitrocellulose as binder,when the binder content increased from20%to25%, the burning time and burning rate of whole grain showed a little change, but as the binder content increased to30%, the combustion time increased obviously,and the combustion rate decreased obviously. Second,as forming pressure increased, combustion rate of whole grain reduced, the burning time increased.The results of the universal material testing machine showed that the binder content and forming pressure can affect both the mechanical properties and the burning performances of whole grain.