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1

Theoretical analysis of the use of glycidyl polyazide and polynitratomethylmethyloxetane in high-performance reduced-smoke rocket propellants

Gołofit Tomasz, Cieślak Katarzyna, Chmielarek Michał

Materiały Wysokoenergetyczne

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2023

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T. 15

36--47

EN

Conducting preliminary calculations of the ballistic effectiveness and smoke generation of new rocket propellant compositions is beneficial due to the high cost of tests. In this work, the combustion temperature (Tcomb.) and specific impulse (Isp) for rocket propellants were determined using the Air Force Specific Impulse Program. The effect of replacing the non-energetic binder hydroxyl terminated polybutadiene (HTPB) with binders containing explosophoric groups with glycidyl polyazide (GAP) or polynitratomethylmethyloxetane (polyNIMMO), and replacing ammonium perchlorate (AP) with ammonium dinitramide (ADN) are discussed. The highest Tcomb. and the highest Isp were obtained for a system containing 20% GAP, 60% ADN and 20% Al. Another important aspect of modern rocket propellants is smoke intensity, so smoke classifications were determined for the proposed compositions in accordance to the classification given in a report by the Advisory Group for Aerospace Research & Development (AGARD). The use of the new components – GAP, polyNIMMO and ADN – is beneficial because it enables a higher Isp and reduced smoke. The maximum Isp of these propellants is obtained for compositions containing higher amounts of binder, which facilitates the manufacturing process. The use of computer calculations in the first phase of research into new rocket propellants makes it possible to estimate the improvement in performance of the new propellant and to learn about the impact of composition changes on performance.

PL

Przeprowadzenie wstępnych obliczeń efektywności balistycznej oraz dymności nowych składów paliw rakietowych jest korzystne ze względu na wysokie koszty badań gotowych wyrobów. W pracy, przy wykorzystaniu programu Air Force Specific Impulse Program wyznaczono temperaturę palenia (Tcomb.) i impuls właściwy (Isp) układów trójskładnikowych zawierających jako utleniacz: chloran(VII) amonu (AP), sól amonową dinitroaminy (ADN), jak lepiszcze: polibutadien zakończony grupami hydroksylowymi (HTPB), poliazydek glicydylu (GAP), poliazotanometylometyloksyetan (NIMMO) oraz glin (Al). Omówiono wpływ zastąpienia nieenergetycznego lepiszcza HTPB, lepiszczami zawierającymi grupy eksplozoforowe oraz zastąpienie AP ADN. Opisano również wpływ Al na temperaturę i Isp omawianych paliw. Najwyższą Tcomb. oraz najwyższy Isp uzyskano dla układu GAP-ADN-Al. Kolejnym istotnym aspektem nowoczesnych paliw rakietowych jest intensywność dymienia. Określono klasy dymienia według klasyfikacji AGARD zaproponowanych składów. Zastosowanie nowych składników GAP, NIMMO i ADN jest korzystne, ponieważ: pozwala na uzyskanie większego Isp oraz zmniejszonego dymienia. Maksimum Isp tych paliw jest uzyskiwane dla składów zawierających większe ilości lepiszcza, co ułatwia proces wytwarzania. Wykorzystanie obliczeń komputerowych w pierwszym etapie badań nad nowymi paliwami rakietowymi pozwala na oszacowanie poprawy parametrów użytkowych nowego paliwa oraz poznanie wpływu zmian składu na parametry użytkowe.

2

Study of Molecular Perovskite (H2dabco)[NH4(ClO4)3]/Carbon Nanotubes Energetic Composite

Hu Li-shuang, Liu Yang, He Dan, Yang Yajun, Gong Shida, Guang Chunyu, Deng Peng, Hu Shuangqi

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 1

91--105

EN

An ammonium perchlorate (AP, NH4(ClO4)3)-based molecular perovskite energetic material (H2dabco)[NH4(ClO4)3]/carbon nanotubes (DAP/CNTs) composite was prepared and characterized. Molecular perovskite DAP samples were synthesized by a facile one-pot reaction of triethylenediamine, perchloric acid (PCA, HClO4), and AP via a molecular assembly strategy. The results showed that the mechanical sensitivity (impact and friction sensitivities: >120 cm and 20%) and electrostatic spark sensitivity (8.90 J) of the DAP/CNTs energetic composite with 10 wt.% CNTs exhibited less sensitivity than that of DAP (impact, friction and electrostatic spark sensitivities: 112.3 cm, 45%, and 5.39 J, respectively), because of the mixing desensitization mechanism of CNTs. Compared with the pure DAP, the DAP/CNTs energetic composite has better performance with respect to thermal stability, exothermic capacity, and excellent continuous combustion properties. The DAP/CNTs energetic composite has potential application in a weapons system.

3

Study of Ammonium Perchlorate-based Molecular Perovskite (H2DABCO)[NH4(ClO4)3]/Graphene Energetic Composite with Insensitive Performance

Liu Yang, Hu Li-shuang, Gong Shida, Guang Chunyu, Li Lianqiang, Hu Shuangqi, Deng Peng

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 3

451--469

EN

In order to improve the safety properties of molecular perovskite energetic materials, ammonium perchlorate-based molecular perovskite ((H2DABCO)[NH4(ClO4)3], DAP)/graphene composite was prepared and characterized. Molecular perovskite DAP was prepared via a molecular assembly strategy by the facile one-pot reaction of triethylenediamine (TEDA, DABCO), perchloric acid, and ammonium perchlorate, and the DAP/graphene composite was fabricated by mechanical mixing with 10 wt.% graphene. The results demonstrated that impact sensitivity (>120 cm), friction sensitivity (25%) and electrostatic spark sensitivity (7.04 J) of the DAP/graphene composite was less sensitive than raw DAP (impact, friction and electrostatic spark sensitivity: 112.3 cm, 45%, and 5.39 J, respectively), due to the composite desensitization mechanism of graphene. This work may offer new ideas for the design and fabrication of insensitive molecular perovskite-based energetic composites.

4

Synthesis, Characterization, and Application of Stabilized-Ni/Fe Bimetallic Nanoparticles for the Selective Elimination of Chlorate Impurity in Military Grade Ammonium Perchlorate

Zarei A. R., Moloudi A., Hosseini S. G.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 1

120--133

EN

Ammonium perchlorate (AP) is used as the most common oxidizer in composite solid propellants. Control of chlorate impurity in military grade ammonium perchlorate is important, since it has an undesirable effect on the thermal decomposition of ammonium perchlorate. In this work stabilized Ni/Fe bimetallic nanoparticles (S-Ni/Fe NPs) were synthesized using the borohydride reduction method (BRM) in the presence of starch as a stabilizing agent, and they were characterized by field emission scanning electron microscopy (SEM), and their X-ray diffraction pattern (XRD). The results showed that the synthesized S-Ni/Fe bimetallic nanoparticles were spherical in shape and had nearly uniform distribution, with particle sizes of 20-50 nm. The prepared nanoparticles were then used for the selective elimination of chlorate impurity in ammonium perchlorate. The main factors controlling the elimination of chlorate, such as the initial pH of the solution, dosage of S-Fe/Ni NPs, initial chlorate and perchlorate concentrations, reaction temperature, and reaction time, were optimized by using an experimental design based on the Taguchi method. An L9 orthogonal array (L9-OA) was used to design experiments with four 4-level factors (34). Under the optimal conditions, i.e., pH 6.5, at 30 °C and a dosage of 50 mg S-Ni/Fe NPs, chlorate was eliminated with nearly 100% efficiency in 50 mL of a solution containing 2.0 μg·mL−1 and 100 μg·mL−1 of chlorate and perchlorate, respectively, without change in perchlorate concentration.

5

Synthesis and Characterization of CuO Nanoparticles by the Chemical Liquid Deposition Method and Investigation of Its Catalytic Effect on the Thermal Decomposition of Ammonium Perchlorate

Eslami A., Juibari N. M., Hosseini S. G., Abbasi M.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 1

152--168

EN

Copper oxide nanoparticles have been synthesized by the chemical liquid deposition method and characterized by means of X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The XRD and SEM results showed that the particle size was between 50 nm and 70 nm. Ammonium perchlorate (AP)-CuO nanostructures have been prepared by ex-situ mixing of AP and CuO nanoparticles, while AP/CuO nanocomposites have been obtained by in-situ growth of nano CuO on the surface of AP. The effect of the nanoparticles on the thermal decomposition of AP has been examined by differential scanning calorimetery (DSC) and thermogravimetric analysis (TGA) methods. The results showed that the ex-situ prepared nanoparticles had better catalytic activity than the in-situ prepared ones. The effect of the synthesized nanoparticles on the thermal decomposition of AP in experiments with a AP to CuO ratio of 98:2 was as follows: with the ex-situ prepared experiments, the decomposition temperature decreased from 428 °C to 348 °C and the heat released increased from 344 J·g−1 to 1432 J·g−1, while those with the in-situ prepared samples exhibited 341 °C and 1317 J·g−1, respectively.

6

Thermal Decomposition Kinetics of Hexanitrohexaazaisowurtzitane/Ammonium Perchlorate

Zhu Y.-L., Wang K.-K., Shan M.-X., Zheng X.-D., Jiao Q.-J., Wang J.-S.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 1

149--159

EN

The thermal decomposition kinetics of hexanitrohexaazaisowurtzitane/ ammonium perchlorate (HNIW/AP) have been investigated by thermogravimetrydifferential scanning calorimetry-mass spectrometry (TG-DSC-MS) simultaneous analysis. TG showed that there were three weight loss processes for the thermal decomposition of the HNIW/AP mixture. The first was ascribed mainly to the thermal decomposition of HNIW, while the second and third were assigned to that of AP. The presence of AP has little effect on the thermal decomposition process of the HNIW component. The apparent activation energy of the thermal decomposition of the HNIW component, calculated by the Kissinger method, was little changed compared to that of neat HNIW. The addition of HNIW to AP caused the onset and end temperatures of the thermal decomposition to be decreased and the decomposition process to be shortened. The high-temperature and lowtemperature decomposition processes of AP became blurred in the presence of HNIW, and this was supported by the MS results.

7

Evaluation of Potassium Perchlorate as a Burning Rate Modifier in Composite Propellant Formulations

Jain S., Mehilal D., Singh P. P., Bhattacharya B.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 1

231--245

EN

The burning rate of a solid composite propellant is one of its most important ballistic properties. To achieve a specified burning rate, transition metal oxides are used as burning rate modifiers. However, addition of transition metal oxides creates inertness in the composition. To avoid such inertness, an attempt has been made to incorporate potassium perchlorate (KP) as a burning rate modifier by partially replacing ammonium perchlorate (AP), up to the 10% level, and the composition was then studied in detail for its mechanical, thermal and ballistic properties. The data revealed that no change occurred in the case of the mechanical properties, however, the thermal stability decreased as the KP content was increased. The burning rate data revealed that on incorporation of 10% KP, there was an enhancement in the burning rate of up to 35% in comparison to the original composite propellant formulation, but beyond this no enhancement in burning rate was observed, indicating that the optimum content for KP in the composition had been reached.

8

The influence of VO2(B) nanobelts on thermal decomposition of ammonium perchlorate

Zhang Y., Tan X., Meng C.

Materials Science Poland

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2015

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Vol. 33, No. 3

560--565

EN

The influence of vanadium dioxide VO2(B) on thermal decomposition of ammonium perchlorate (AP) has not been reported before. In this contribution, the effect of VO2 (B) nanobelts on the thermal decomposition of AP was investigated by the Thermo-Gravimetric Analysis and Differential Thermal Analysis (TG/DTA). VO2 (B) nanobelts were hydrothermally prepared using peroxovanadium (V) complexes, ethanol and water as starting materials. The thermal decomposition temperatures of AP in the presence of 1 wt.%, 3 wt.% and 6 wt.% of as-obtained VO2( (B) nanobelts were reduced by 39 °C, 62 °C and 74 °C, respectively. The results indicated that VO2 (B) nanobelts had a great influence on the thermal decomposition temperature of AP. Furthermore, the influence of the corresponding V2O5, which was obtained by thermal treatment of VO2 (B) nanobelts, on the thermal decomposition of AP was also investigated. The results showed that VO2 (B) nanobelts had a greater influence on the thermal decomposition temperature of AP than that of V2O5.

9

Formation of Tungsten/Ammonium Perchlorate Composites and Their Reaction Kinetics

Shim H.-M., Lee E.-A., Kim J.-K., Kim H.-S., Koo K.-K.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 4

703--722

EN

The reaction kinetics of tungsten nanoparticles/ammonium perchlorate (W/AP) composites, produced by a spray drying technique, were analyzed and compared with those of neat AP particles and aluminum nanoparticles/AP (Al/AP) composites. The W was found to raise the onset temperature of the thermal decomposition of AP by increasing the activation energy, whereas Al conversely lowered the onset temperature of AP due to the decreased activation energy. From the master plots of kinetic models with the experimental data, the Prout-Tompkins model and the 1-D diffusion controlled model were found to describe the low-temperature decomposition (LTD) and high-temperature decomposition (HTD), respectively, giving remarkable agreement with experimental curves for all heating rates. The presence of W was found to increase the HTD zone width compared with that of neat AP particles and Al/AP composites. Analysis of the average activation energy and pre-exponential factor showed that W increases the energy barrier and the frequency of occurrence of the reaction compared with that of neat AP particles at the LTD state, whereas W decreases both of them at the HTD state. The effect of Al was also shown to be similar to that of W, but the magnitudes of the variation in activation energy and the pre-exponential factor were relatively small.

10

Studies on High Burning Rate Composite Propellant Formulations using TATB as Pressure Index Suppressant

Mehilal, Jawalkar S., Kurva R., Sundaramoorthy N., Dombe G., Singh P. P., Bhattacharya B.

Central European Journal of Energetic Materials

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2012

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Vol. 9, nr 3

237-249

EN

High burning rate propellant compositions are generally used in gas generators to eject missile from canister. Because of high burning rate, pressure index of the composition increases during burning. To reduce the pressure index, a high burning rate composite propellant formulations (~20 mm/s) based on AP/HTPB/Al have been prepared by incorporating TATB and studied in detail for viscosity build-up, thermal and mechanical properties, sensitivity as well as burning rate and pressure index (n). The data indicate that there is a decrease in end of mix viscosity on increasing the percentage of TATB. The same trend was also observed with mechanical properties while significant improvement in overall thermal stability was clearly observed. The sensitivity data indicate that impact and friction values show decreasing trend infer better safe to handle. The burn rate data reveal that on addition of TATB from 0.5 to 2% decrease in burning rate was not observed while on addition of further TATB up to 5% and beyond this significant decrease in burning rate was observed. The data on pressure index (n) also reveal that TATB is very effective in reducing the 'n' value up to 2% and beyond this 'n' value increases close to standard composition. The data on 'n' value reveal that it reduces from 0.47 to that of standard composition to 0.36 for the compositions containing TATB up to 2.0% in the pressure range of 60-90 kg/cm2.

11

Impact Initiation of Compositions Ammonium Perchlorate with Inorganic Components

Dubovik A. V., Kokovikhin D. V.

Central European Journal of Energetic Materials

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2010

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Vol. 7, nr 4

325-334

EN

Experimental data on sensitivity to impact of compositions ultra- and nanodispersed AP with inorganic components are presented. Critical parameters of impact initiation of these compositions lay down on the straight line in co-ordinates (ecr, Pcr2) characterising balance of energy at the impact.