مجله تحقیق و توسعه مواد پرانرژی
سال چهاردهم شماره 2 (پیاپی 32، پاییز و زمستان 1397)

How to thermal decomposition of ammonium perchlorate and the energy realeased from it’s decomposition is effective on the burning rate of propellant.Therefore, various catalysts can be used to improve the combustion properties of ammounium perchlorate .Crystalline transition metal oxides (TMOs) with diverse morphological structure have attracted tremendous attention during the last decade. Among the TMOs catalysts, copper chromite (CuCr2O4) for several reasons including the spinel crystalline structure and arrangement of copper atoms in its structure have special importance. CuCr2O4 nanoparticles, as catalyst are widely used in military and other industries to improve burning rate of solid propellant, hydrogenation reactions, oxidation, alkylation, cyclization, organic waste removal from aqueous wastes, production of pharmaceuticals and etc. Due to the wide range of applications, the synthesis of this compound is very important. In this paper, it is aimed to review synthesis methods, Quantitative and qualitative control methods and also comparing synthesis methods with industrial approach with focusing on solid composite propellants, have been discussed.

Liquid fuels usually have low electrical conductivity leads to accumulating in static electricity during transmission, mixing and spraying processes. This charge accumulation will spark and fire if it exceeds the air ionization energy. Therefore, one of the important parameters in fuels safety is their potential for static charge accumulation. In this manuscript, materials are classified into static electricity and the mode of generation, accumulation, discharge and distribution of electric charge in liquid fuels will be investigated. Then, solutions for static electricity control in low conductivity high energetic liquids presented. Finally, common methods of measuring the static electricity presented.

Hydroxyl terminated polybutadiene (HTPB) is a low molecular weight polymer which has used in various industries. The good mechanical and thermal properties of HTPB based polyurethane is caused to use it as a binder for the solid composite propellants and plastic bonded explosives. Also, The presence of double bonds and hydroxyl end groups in the structure of HTPB can provide an opportunity to improve its properties through chemical modification by various reactant and develop its application. In this paper, we classify and study the chemical modification of HTPB under the basis of the reactions were carried out on the carbon-carbon double bond, terminal hydroxyl group and terminal carbon atoms of hydroxyl terminated polybutadiene.

The mechanical properties of the final energetic composite depend mainly on the HTPB prepolymer microstructure; thus, the prepolymer microstructure of HTPB is one of the important factors influencing the mechanical properties of highenergy composite based on HTPB resin. In this paper, the effect of microstructure parameters of HTPB on the behavior and mechanical properties of its high-energy composite has been investigated. The difference in the production of these polymers, as well as their variability, leads to the formation of various polymers in the microstructure parameters of HTPB (molecular weight distribution and factor distribution). These differences often affect the processability, lifetime of the appliance, the behavior of cooking, and especially the mechanical properties of high-energy composites. Using various grades of HTPB has various microstructural parameters, in order to achieve the optimal mechanical properties with high bar resistance according to the results, there is a need to understand the microstructure of the binder, namely, prepolymer. The studies carried out in this paper show that with increasing molecular weight of HTPB, tensile strength, modulus, rupture resistance and hardness decrease, and by decreasing the high molecular weight component of HTPB, the exponential and high-energy composite modulus increases. There is a linear relationship between the amount of hydroxyl and the mechanical properties of the tensile strength and modulus.

As energy weapon carriers, high energy materials are of particular importance. Increasing explosive performance along with increased immunity or reduced sensitivity are the main goals of the field of research on high energy materials, but the increase in performance is somewhat contradictory with decreasing the sensitivity which should be followed by a balance between them. In designing new high performance molecular structures and low sensitivity, it is necessary to identify the factors affecting on sensitivity and consider them in design. In this paper, the factors affecting on sensitivity have been investigated from three perspectives, molecular, physical and crystalline factors that affect sensitivity, as well as strategies that can help to reduction the sensitivity of explosives without significantly reducing of performance.

Chain extenders are diols or small diamines that enter the polyurethane hard parts through chemical reactions. N, N -bis(2- hydroxypropyl) aniline (Isonol C100) and bis (2-hydroxyethyl) aniline as the most important chain-extender in the curing of propellant solids composite, stabilizers and plasticizers in the propellants system double and also as a co-plasticizers in ethyl cellulose. It can be said that the most important application of this compounds is in polyurethanes. In the synthesis of rubber-like polyurethanes (sticky), it is used to strengthen, and extend the length of the chain. In the structure of these compounds, there is a benzene ring that increases the strength of the product. On the other hand, there is also a third type of amine in the skeleton, which increases the mechanical properties of the polyurethane. In this study will investigate the synthesis methods of bis (2-hydroxypropyl) aniline (Isonol C100) and bis (2-hydroxyethyl) aniline. Many of the methods have used aniline, ethylene oxide or 2-chloroethanol to synthesize bis (2-hydroxyethyl) aniline and propylene oxide and aniline to synthesize Isonol C100.

Promote chemical technologies is an innovation that reduce or eliminate use or production of hazardous materials in the design, manufacture and use of chemical products. According to this law, reduce pollution at source is fundamentally different and more desirable than waste management and pollution control. Nowadays, this new approach known as green chemistry, which is: The design of chemical products and processes that reduce or destroy use and generate substances harmful to human health and the environment. In this article, chemical compounds containing the new tetrazoles includes N- oxide group, which belongs to high energetic compounds, has been discussed and compared with conventional explosives. In this comparison, it is seen that some -N-oxide compounds have better properties and performance compared to conventional explosives. So they could be suitable alternatives for propellants and explosives.