Showing papers on "Ammonium perchlorate published in 2012"
TL;DR: In this article, nano-sized CuO, Co 3 O 4 and CuCo 2 O 4 powders were prepared via different methods such as co-precipitation, thermal decomposition of oxalate precursor and sol-gel and their catalytic activities towards thermal deformation of ammonium perchlorate.
234 citations
TL;DR: In this article, an attempt to collect the summarised data of literature on catalytic effect of nano-oxides, such as mono oxides, mixed oxide, binary and ternary ferrites and rare earth metal oxides on the thermal decomposition of ammonium perchlorate (AP) is made.
Abstract: In this review, an attempt to collect the summarised data of literature on catalytic effect of nano-oxides, such as mono oxides, mixed oxide, binary and ternary ferrites and rare earth metal oxides on the thermal decomposition of ammonium perchlorate (AP) is made. Influence of size effect of oxides on thermal decomposition of AP and comparison of bulk and nanosized oxides is also discussed here. Several experimental results revealed that due to small size and large surface area nanosized metal oxides are more potential catalysts on thermal decomposition of AP compared to their bulk size oxides.
94 citations
TL;DR: In this article, mesoporous β-MnO2 has been demonstrated to possess excellent catalytic activity in the thermal decomposition of ammonium perchlorate and was used as a highperforming ballistic modifier in composite solid rocket propellants.
Abstract: Mesoporous β-MnO2 has been prepared, characterized and demonstrated to possess excellent catalytic activity in the thermal decomposition of ammonium perchlorate. The observed unprecedentedly low decomposition temperatures, fast reaction rates and enhanced heat releases in the catalysed formulations make mesoporous β-MnO2 promising as a high-performing ballistic modifier in AP-based composite solid rocket propellants.
91 citations
TL;DR: In this paper, shape-controlled synthesis of cobalt-II-based coordination polymer particles has been reported, where three different structures of flower-like architectures, multilayer stacked structures and nanosheets have been synthesized by varying the volume ratio of ethanol and water.
Abstract: In this paper, we report a facile approach for the shape-controlled synthesis of cobalt(II)-based coordination polymer particles. Three different structures of flower-like architectures, multilayer stacked structures and nanosheets have been synthesized by varying the volume ratio of ethanol and water. Phase-pure Co3O4 nanocrystals have been obtained by annealing the coordination polymer particles without significant alterations in morphology. The products have been characterized by X-ray diffraction techniques, field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The catalytic effect was investigated for the Co3O4 nanocrystals with different morphology on the thermal decomposition of ammonium perchlorate (AP) and it was found that the Co3O4 nanosheet has the highest catalytic activity. The surface areas of Co3O4 nanocrystals are measured by the Brunauer–Emmett–Teller (BET) technique and the results show that the catalytic activity of Co3O4 nanocrystals for the thermal decomposition of AP increases with the increase of BET surface area and pore volume.
66 citations
TL;DR: In this paper, the synthesis of Cu nanoparticles by reducing CuSO 4 with hydrazine in ethylene glycol under microwave irradiation, has been described, and the catalytic activity, of CU nanoparticles on thermal decomposition of ammonium perchlorate (AP), composite solid propellants (CSPs) using thermogravimetry (TG), differential scanning calorimetry(DSC) have been measured.
66 citations
TL;DR: In this article, a combustion model controlled by condensed-phase reactions (c-phase combustion model) is considered, based on an analysis of numerous thermocouple studies of combustion of energetic materials, it is shown that the condensed phase is heated in the combustion wave to the maximum possible temperature.
Abstract: A combustion model controlled by condensed-phase reactions (c-phase combustion model) is considered. Based on an analysis of numerous thermocouple studies of combustion of energetic materials, it is shown that the condensed phase is heated in the combustion wave to the maximum possible temperature—the boiling point at this pressure. It is established that the combustion of representatives of the class of onium salts such as ammonium perchlorate, ammonium nitrate, ammonium dinitramide, and hydrazinium nitroformate over a wide range of pressures and initial temperatures obeys the the c-phase-model. The kinetic parameters of the burning-rate controlling reaction of these salts are given.
48 citations
TL;DR: The catalytic effect of catalysts on ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene (HTPB) propellant was studied in this article.
46 citations
TL;DR: An in-depth insight into the thermal decomposition mechanism of AP as catalyzed by oxalates is provided and it is believed that it is the "self-crushing and self-distributed" occurred within the reaction that really works for the improvement of the overall catalytic activities.
43 citations
TL;DR: In this paper, the authors provide a detailed discussion of relevant work on the multidimensional computational simulation of heterogeneous solid propellant combustion, focusing on composite solid propellants and plastic-bonded explosives.
Abstract: H ETEROGENEOUS solid energetic materials are widely used in the aerospace and defense industries in rockets, explosives, and diverse pyrotechnic devices. Their basic microstructure consists of oxidizer particles embedded in a polymeric binder. Two important classes of energeticmaterials are solid propellants and plastic bonded explosives. A typical composite solid propellant is composed ammonium perchlorate (AP) particles embedded in a polymer such as hydroxyl-terminated polybutadiene (HTPB) or polybutadiene acrylonitrile. A common variation is the addition of metal particles (e.g., aluminum) to raise the combustion temperature. Plastic bonded explosives consist of a heterogeneous mixture of high-explosive crystals (such as cyclotetramethylenetetranitramine or cyclotrimethylenetrinitramine) and a polymeric binder. Here, the discussion is restricted to composite solid propellants. The intent of the present survey is to provide a highlighted discussion of relevant work on the multidimensional computational simulation of heterogeneous solid propellant combustion. Routine numerical simulations are now being carried out, in which many of the physical characteristics of real propellants are mimicked, including random packing of oxidizer particles in a fuel binder, unsteady three-dimensional heat conduction within the solid, unsteady regressionof thenonplanar propellant surface, andcoupling with an unsteady three-dimensional combustion field sustained by reactantfluxes from the surface. Such computations require the use of massively parallel supercomputers, and even then there are limitations onwhat physics can be included. The ultimate goal is to develop a truly predictive simulation tool that can assist in design and optimization of propellant microstructures and propellant grain designs for internal solid rocket motors. Modeling and simulation of composite propellants will remain a vital task because solid rocket motors are critical to national defense, communications, space exploration, and eventually space tourism. The value of computational combustion is eloquently presented in a recent review paper [1]. II. Modeling
43 citations
TL;DR: In this article, CoCO3 particles with diverse morphologies were successfully synthesized through a solvothermal method using cobalt salt and urea as reactants with the assistance of sodium dodecylsulphonate Co3O4 particles which kept the spherical morphology were obtained by a subsequent calcinating process at a series of temperatures from 350 to 550°C.
37 citations
TL;DR: In this article, an energetic coordination compound, Cu(HATZ)(PDA)(H2O), has been synthesized and structurally characterized by single crystal X-ray diffraction.
Abstract: An energetic coordination compound, Cu(HATZ)(PDA)(H2O) (HATZ = 5-aminotetrazole, H2PDA = pyridine-2,6-dicarboxylic acid), has been synthesized and structurally characterized by single crystal X-ray diffraction. Copper(II) was coordinated by two oxygen atoms and nitrogen from PDA, one ring nitrogen of ATZ and one water to form a five-coordinate, distorted square-pyramidal structure. 3-D supramolecular architecture was formed by hydrogen bonding. Thermal decomposition of the compound was examined by DSC and TG-DTG analyses. The kinetic parameters of the first exothermic process of the compound were studied by Kissinger's and Ozawa–Doyle's methods. Sensitivity tests revealed that the compound was insensitive to mechanical stimuli. In addition, the compound was explored as additive to promote thermal decomposition of ammonium perchlorate by differential scanning calorimetry.
TL;DR: In this article, an attempt to collect the summarised data of literature on catalytic effect of nano-oxides, such as mono oxides, mixed oxide, binary and ternary ferrites and rare earth metal oxides on the thermal decomposition of ammonium perchlorate (AP) is made.
Abstract: In this review, an attempt to collect the summarised data of literature on catalytic effect of nano-oxides, such as mono oxides, mixed oxide, binary and ternary ferrites and rare earth metal oxides on the thermal decomposition of ammonium perchlorate (AP) is made. Influence of size effect of oxides on thermal decomposition of AP and comparison of bulk and nanosized oxides is also discussed here. Several experimental results revealed that due to small size and large surface area nanosized metal oxides are more potential catalysts on thermal decomposition of AP compared to their bulk size oxides.
TL;DR: In this article, a procedure for the preparation of spherical Cr(OH)(3) nanoparticles was developed based on the aging of chromium nitrate aqueous solutions in the presence of sodium fluoride, urea, and polyvinylpyrrolidone.
TL;DR: In this article, a V 2 O 3 /carbon core-shell structured composite was successfully synthesized using V 2O 5 and glucose as the starting materials by a facile hydrothermal route and subsequent calcinations at 700°C for 2°h under Ar atmosphere.
Abstract: A V 2 O 3 /carbon core-shell structured composite (V 2 O 3 /C) was successfully synthesised using V 2 O 5 and glucose as the starting materials by a facile hydrothermal route and subsequent calcinations at 700°C for 2°h under Ar atmosphere. The as-obtained products were characterised by X-ray powder diffraction, energy-dispersive X-ray spectrometer, elemental analysis, Fourier transform infrared spectroscopy, Raman spectrum, scanning electron microscopy and transmission electron microscopy. Furthermore, V 2 O 3 and V 2 O 3 /C were explored as the additives to the thermal decomposition of ammonium perchlorate (AP), the key component of composite solid propellants. The thermal decomposition temperatures of AP in the presence of V 2 O 3 and V 2 O 3 /C were reduced by 49 and 73°C, respectively, which indicates that V 2 O 3 /C has higher activity than that of V 2 O 3 .
TL;DR: In this article, NiAl-layered double hydroxide/carbon (LDH/C) nanocomposites were prepared by a hydrothermal process simultaneously involving the crystallization of LDH and carbonization of glucose.
TL;DR: In this article, the authors showed that capture is dependent on antisol- vent-to-solvent ratio; increased quantities of antisolvent lead to faster nucleation rates, smaller crystals, and proved capture, while the crystal habit formation is modified by the addition of nanoparticles, resulting in highly uniform rod-like crystal structures.
Abstract: Energetic crystals with nanoparticle inclusions were preparated and characterized, focusing on the nano- sized iron(III) oxide-ammonium perchlorate system, gener- ated using an ethyl acetate/acetone antisolvent:solvent system. It is shown that capture is dependent on antisol- vent-to-solvent ratio; increased quantities of antisolvent lead to faster nucleation rates, smaller crystals, and im- proved capture. Additionally, the crystal habit formation is modified by the addition of nanoparticles, resulting in highly uniform rod-like crystal structures. Results with nanoaluminum-ammonium perchlorate and nanoalumi- num-cyclotrimethylenetrinitramine (RDX) systems have shown similar capture behavior.
29 Jun 2012
TL;DR: In this paper, the properties and characteristics of nano-sized aluminum particles in propellants are discussed, focusing on their properties and properties pertaining to their combustion and their attractability in terms of their propulsion properties.
Abstract: Energetic materials have been widely used for military purposes. Continuous research programs are performing in the world for the development of the new materials with higher and improved performance comparing with the available ones in order to fulfill the needs of the military in future. Different sizes of aluminum powders are employed to produce composite rocket propellants with the bases of Ammonium Perchlorate (AP) and Hydroxyl-Terminated-Polybutadiene (HTPB) as oxidizer and binder respectively. This paper concentrates on recent advances in using aluminum as an energetic material and the properties and characteristics pertaining to its combustion. Nano-sized aluminum as one of the most attractable particles in propellants is discussed particularly.
TL;DR: In this article, a multiscale modeling and analysis of solid propellants is presented, where a homogenization theory is employed to compute the mean stress and strain of a representative volume element (RVE), and a suitable size of RVE is decided.
Abstract: In the present work, a computational framework is established for multiscale modeling and analysis of solid propellants. A packing algorithm, considering the ammonium perchlorate (AP) and aluminum (Al) particles as spheres or discs is developed to match the size distribution and volume fraction of solid propellants. A homogenization theory is employed to compute the mean stress and strain of a representative volume element (RVE). Using the mean results, a suitable size of RVE is decided. Without considering the interfaces between particles and matrix, several numerical simulations of the relaxation of propellants are performed. The relaxation effect and the nonlinear mechanical behavior of propellants which are dependent on the applied loads are discussed. A new technology named surface-based cohesive behavior is proposed to describe the phenomenon of particle dewetting consisting of two ingredients: a damage initiation criterion and a damage evolution law. Several examples considering contact damage behavior are computed and also nonlinear behavior caused by damaged interfaces is discussed in this paper. Furthermore the effects of the critical contact stress, initial contact stiffness and contact failure distance on the damaged interface model have been studied.
TL;DR: In this paper, the catalytic activity of copper oxalate nanocrystals (CONs) on the thermal decomposition of ammonium perchlorate (AP) and composite solid propellants (CSPs) has been investigated.
TL;DR: In this article, three new cobalt(II) coordination compounds, [Co(3,3′-Hbpt)2(H2pm)(H2O)2]·2H 2O (1), [Co[Co(4,4′-hbpt)(pm)0.5(H 2 O 2 O)]·3,4,5-bis(4-pyridyl)-1H-1,2,4-triazole,
Abstract: Three new cobalt(II) coordination compounds, [Co(3,3′-Hbpt)2(H2pm)(H2O)2]·2H2O (1), [Co(4,4′-Hbpt)(pm)0.5(H2O)]·3H2O (2) and [Co(3,4′-Hbpt)(pm)0.5(H2O)3]·2H2O (3) (3,3′-Hbpt = 3,5-bis(3-pyridyl)-1H-1,2,4-triazole; 4,4′-bpt = 3,5-bis(4-pyridyl)-1H-1,2,4-triazole, 3,4′-Hbpt = 3-(3-pyridyl)-5-(4′-pyridyl)-1H-1,2,4-triazole and H4pm = pyromellitic acid) have been synthesized by hydrothermal reactions. Single-crystal X-ray diffraction reveals that compound 1 has a one-dimensional (1D) chain network, 2 exhibits a four-connected three-dimensional (3D) structure with 1D open channels encapsulated by water molecules, while 3 displays a regular two-dimensional (2D) architecture connected through 1D metal helical chains. In addition, the efficacy of compounds 1–3 as additives to promote the thermal decomposition of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC).
Journal Article•
TL;DR: In this article, the authors investigated the thermal decomposition of AP/GA nanocomposites and found that the high temperature decomposition peak temperature decreases by 83.7℃ and the total heat release reaches 2 110 J/g.
Abstract: Ammonium perchlorate / graphene aerogels(AP/GA) nanocomposites were prepared by sol-gel method and characterized by scanning electron microscope(SEM),elemental analysis and X-ray diffraction(XRD).Their thermal decomposition behaviours were investigated by TG-DSC-IR.The results indicate that AP is presented in the AP/GA nanocomposites with an average particle size of 69.41 nm and occupied 94.4% of total mass.GA shows an obvious catalytic effect on the thermal decomposition of AP/GA.Compared to pure AP,the low temperature decomposition peak of AP/GA nanocomposites disappears,the high temperature decomposition peak temperature decreases by 83.7℃,and the total heat release reaches 2 110 J/g.
TL;DR: In this article, a series of Cu/Cr nanocomposite oxides (Cu/Cr-NCOs) were prepared by hydrotalcite precursors and their catalytic activities on thermal decomposition of ammonium perchlorate (AP) were investigated by differential thermal analysis.
Abstract: A series of Cu/Cr nanocomposite oxides (Cu/Cr–NCOs) were prepared by Cu/Cr hydrotalcite precursors. Their catalytic activities on thermal decomposition of ammonium perchlorate (AP) were investigated by differential thermal analysis (DTA). The results show that Cu/Cr–NCOs are efficient in enhancing thermal decomposition of AP. With 4 wt. % addition of 500 °C calcined Cu2Cr–NCOs, the thermal decomposition process of AP can be accelerated by 107 °C. Cu/Cr–NCOs catalysts have better effect compared to mechanical mixture of CuO and Cr2O3 catalyst. Their catalytic mechanism was also discussed.
TL;DR: Magnesium nanopowder (MgNP) of 17nm average size was produced by planetary ball milling of Mg ( ϕ =229μm) with 10% NaCl (ϕ =406 ǫ) for 50h as mentioned in this paper.
Patent•
06 Mar 2012
TL;DR: In this article, a propellant composition consisting of hydroxy-terminated polyether (HTPE), N-butyl-(2-nitratoethyl)nitramine (BuNENA) and ammonium perchlorate (AP) is proposed.
Abstract: The present invention relates to a propellant composition which comprises hydroxy-terminated polyether (HTPE), N-butyl-(2-nitratoethyl)nitramine (BuNENA) and ammonium perchlorate (AP) and is insensitive to impact and thermal reactions and thus suitably used for a solid rocket propulsion unit.
Patent•
27 Jun 2012
TL;DR: In this article, a core-shell nano-composite material and its preparation method is described, which is formed by compounding ammonium perchlorate (AP) and a nano-metal oxide which accounts for 0.1-10% by mass.
Abstract: The invention discloses a core-shell nano-composite material and its preparation method. The composite material is formed by compounding ammonium perchlorate (AP) and a nano-metal oxide which accounts for 0.1-10% by mass. The preparation comprises: (1) dissolving a metal salt in ethyl acetate, and conducting ultrasonic oscillation to make it fully dissolved so as to obtain a metal salt solution, in which the molar concentration of the metal salt is 0.0004-0.04mol/L; (2) adding ammonium perchlorate into the metal salt solution in an undissolved state, and carrying out stirring at room temperature so as to make the ammonium perchlorate dispersed uniformly; (3) using an alkaline solution with an OH ion concentration of 0.1-1mol/L for titration at a constant speed so as to make the metal ions in the metal salt converted to a precipitate completely; and (4) filtering the obtained precipitate and conducting washing, and drying the obtained powder, thus obtaining the core-shell nano-composite material. The metal salt can be ZnCl2, FeCl3, Co(NO3)2.6H2O or CuCl2. In the invention, the dispersion problem of a nano-oxide catalyst in AP is solved; an oxide catalyst is generated on AP in situ, and the oxide content is adjustable; the nano-composite material of the invention has self-catalysis property, and the catalysis effect is substantial.
TL;DR: In this article, a dynamic mechanical analyser (DMA) was used to evaluate the dynamic mechanical properties and quantify the storage life of four different propellants based on hydroxyl terminated polybutadiene, aluminium and ammonium perchlorate having different burning rates ranging from 5 mm/s to 25mm/s, each sample was given a multi-frequency strain of 0.01 per cent at three discrete frequencies (3.5 Hz, 11 Hz, 35 Hz).
Abstract: Propellants, visco-elastic in nature, show time and temperature dependent behaviour on deformation. Hence, the time–temperature superposition principle may be applied to the visco-elastic properties of propellants. In the present study, dynamic mechanical analyser (DMA) was used to evaluate the dynamic mechanical properties and quantify the storage life of four different propellants based on hydroxyl terminated polybutadiene, aluminium and ammonium perchlorate having different burning rates ranging from 5 mm/s to 25 mm/s. Each sample was given a multi-frequency strain of 0.01 per cent at three discrete frequencies (3.5 Hz, 11 Hz, 35 Hz) in the temperature range - 80 °C to + 80 °C. The storage modulus, loss modulus, tan delta and glass transition temperature (Tg) for each propellant samples have been evaluated and it is observed that all the propellants have shown time (frequency) and temperature dependent behaviour on deformation. A comparison of the log aT versus temperature curves (where aT is horizontal (or time) shift factor) for all four propellants indicate conformance to the Williams–Landel–Ferry (WLF) equation. The master curves of storage modulus (log E versus log ω plots) were generated for each propellant. A plot of E versus time for all propellants was generated up to 3 years, 6 years, and 10 years of time, respectively. The drop in the storage modulus below the acceptable limit with time may be used to predict the shelf life of the propellant. Defence Science Journal, 2012, 62(5), pp.290-294 , DOI:http://dx.doi.org/10.14429/dsj.62.2480
TL;DR: In this article, an experimental investigation was carried out to explore the major physical and chemical properties of expanded barium nitrate with porous structure, and the method is as follows: moderately evaporate the solution of barium and inorganic vesicant; heat the crystallized mixture to decompose the inorganic Vesicants.
Abstract: An experimental investigation was carried out to explore the major physical and chemical properties of expanded barium nitrate. Expanded barium nitrate with porous structure was made. The method is as follows: moderately evaporate the solution of barium nitrate and inorganic vesicant; heat the crystallized mixture to decompose the inorganic vesicants. The inorganic vesicants are potassium carbonate, sodium carbonate, ammonium carbonate, ammonium oxalate, potassium acetate, ammonium acetate and ammonium perchlorate. The SEM shows that the modified barium nitrate with potassium carbonate has obvious porous structure. The bulk density of the modified barium nitrate with ammonium perchlorate decreases by 14.6% and the hygroscopicity of that with ammonium oxalate is only 0.06%. The one with sodium carbonate decomposes at 300°C. The safety test shows that both the impact sensitivity and friction sensitivity are 0%.
09 Jan 2012
TL;DR: In this article, the diffusion flame combustion behavior of several solid oxidizers (ammonium nitrate, phase-stabilized ammonium nitrates, ammonium perchlorate and ammonium dinitramide) in combination with a hydrocarbon fuel (ethylene) was examined.
Abstract: The diffusion flame combustion behavior of several solid oxidizers (ammonium nitrate, phase-stabilized ammonium nitrate, ammonium perchlorate, and ammonium dinitramide) in combination with a hydrocarbon fuel (ethylene) was examined. The oxidizers were first analyzed by differential scanning calorimetry, thermal gravimetric analysis, and evolved gas analysis to gain an understanding of their basic decomposition characteristics. Next, an opposed flow burner was used to establish a diffusion flame between the decomposition products of the oxidizer(s) and the fuel. Regression rates of the solid oxidizer were measured by a linear variable displacement transducer as a function of fuel flow rate. Ammonium dinitramide demonstrated the highest linear regression rate characteristics by up to two orders of magnitude, followed by ammonium perchlorate, phase-stabilized ammonium nitrate, and finally ammonium nitrate. When comparing mass burning rates, ammonium perchlorate compares favorably to solid fuels such as hydro...