Summary: | Composite propellants are non-homogenous propellants and comprise primarily crystalline oxidizer and metal fuels uniformly suspended in a resin binder. The strength of the bonds between the polymer matrix and the oxidizer determine the mechanical properties of composite propellants. In order to achieve good mechanical properties of the fuel, bonding agents are added to the mixture. The role of the bonding agents is to enable good interactions (interphase) between the polymer matrix and the oxidizer grains. The level of interconnection between the phases could be measured by using the surface obtained by cutting the composite material and observing the resulting surface. A problem in the visualization of such a material is to enable the visibility of the polymer matrix and the grains in the image as both phases are white. There are two possible ways to overcome this problem: to add a pigment into the matrix polymer and to color the matrix and make it different from the grain color. Another possibility is to find a solvent for one of the phases and to dissolve one of the phases in an appropriate solvent so that the remaining phase could be stained, photographed and analyzed using the image analysis program. The morphological characteristics of the image could be established and analyzed. The topic of this study was to establish the conditions of preparation of composite propellants containing ammonium per chlorate and HMX and RDX as oxidizers, and polymer of the polybutadiene type and 1,3,5-trisubstituted isocyanurates as bonding agents. The bonding phenomenon was investigated by optical microscopy. The established procedure of preparation will enable the visualization of the composite structure and the morphological characteristics of the surface will be obtained. From the morphological properties of the obtained composite, it will be possible to select a suitable polymer for the preparation of uniformly distributed composite propellant.
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