{"title":"Interactions between a neutral polymeric bonding agent and nitramine explosives and their influencing factors","authors":"","doi":"10.1016/j.enmf.2024.03.002","DOIUrl":"10.1016/j.enmf.2024.03.002","url":null,"abstract":"<div><div>Neutral polymer bonding agents (NPBAs) have proven highly effective in enhancing the interfacial bonding between the bonding matrix and nitramine explosives such as cyclic trimethylene trinitramine (RDX) and cyclic tetramethylene trinitramine (HMX). However, there is a lack of clear understanding of the mechanisms behind their interactions, and it has been found that NPBAs produce different interfacial bonding effects on RDX and HMX. To gain deeper insights into the molecular-scale interfacial interactions of nitramine explosives/NPBAs, this study investigated the molecular electrostatic potentials, intermolecular interactions, surface structural features, and interfacial adsorption of a NPBA onto nitramine explosives using the density functional theory and molecular dynamics (MD) technique. The results indicate that the N atom on the cyano group of the NPBA molecule can form weak hydrogen bonds C–H⋅⋅⋅N<img>C and C–H⋅⋅⋅O with the H atoms in the RDX and HMX molecules. The strength of such weak hydrogen bonding interactions is affected by the electrostatic potential range of nitramine molecules. Additionally, the surface structure of the nitramine plays a critical role in the NPBA adsorption strength. Compared to HMX, RDX exhibits a narrower surface electrostatic potential range and smoother crystal surface, resulting in weaker intermolecular interactions between the NPBA and the RDX surface.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140128445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Real-time X-ray diffraction measurement on laser shock-loaded hexanitrostilbene (HNS)","authors":"","doi":"10.1016/j.enmf.2024.04.002","DOIUrl":"10.1016/j.enmf.2024.04.002","url":null,"abstract":"<div><div>Understanding the lattice evolution of hexanitrostilbene (HNS) is crucial for ensuring its safety and reliability under shock loading. However, the lack of <em>in situ</em>, real-time diagnostics has limited the availability of lattice parameters for shock-loaded explosives. In this study, we utilized dynamic X-ray diffraction technology to obtain the diffraction spectrum of laser shock-loaded HNS and to determine its temporal evolution. Additionally, by improving the laser energy, we initiated HNS and obtained the diffraction spectrum of detonation products during the detonation process. The experimental results showed the presence of a diamond structure in the detonation product, suggesting the existence of either diamond or diamond-like carbon. Our research not only elucidates the crystal structure of shock-loaded HNS and its detonation products but also provides an avenue for laboratory-scale investigations into dynamically loaded explosives, which furnishing an opportunity to unveil the underlying mechanism governing explosive dynamic response behavior.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141056347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of inkjet printing using micro-nano CL-20-based PVA colloidal suspension with desensitization to MEMS-based pyrotechnics","authors":"","doi":"10.1016/j.enmf.2023.06.004","DOIUrl":"10.1016/j.enmf.2023.06.004","url":null,"abstract":"<div><div>The micro-scale detonation sequence prepared by the inkjet printing using all-liquid 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazawurtzitan (CL-20)-based energetic inks enables the micro-space fine-scale assembly and stable propagation of detonation. However, the easy crystallization and high mechanical sensitivity of all-liquid CL-20 limit its applications to the microelectromechanical system (MEMS)-based pyrotechnics. This study developed a simple micro-nano CL-20-based polyvinyl alcohol (PVA) colloidal suspension suitable for inkjet printing to control the crystal structures and mechanical sensitivities of energetic composites. The results show that the CL-20-based multilayer films formed by inkjet printing had dense microstructures, with the porosity decreasing to 13.81% and ε-type crystals. Compared with micro-nano CL-20 particles, the impact and friction sensitivities of CL-20-based multilayer films were reduced by 100% and 122%, respectively, and their apparent activation energy increased by 44.7 kJ mol<sup>−1</sup>, thus effectively improving the safety performance of micro-nano structured explosive agents. Therefore, CL-20-based multilayer films have great potential for application to the micro-scale detonation sequence of MEMS.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43058995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dual control over the reignition and combustion performance of hydroxylammonium nitrate-based gel propellants","authors":"","doi":"10.1016/j.enmf.2024.03.005","DOIUrl":"10.1016/j.enmf.2024.03.005","url":null,"abstract":"<div><div>Hydroxylammonium nitrate (HAN; NH<sub>3</sub>OH <sup>+</sup> NO<sub>3</sub><sup>−</sup>), a green and non-toxic monopropellant, finds wide application in liquid and controllable solid propulsion. Gel propulsion enjoys advantages such as a high throttling capacity and encouraging operational safety. This study prepared three HAN-based gel propellant samples with gelling agent contents ranging from 2 to 4 wt%. Their decomposition processes were analyzed using thermogravimetry (TG), differential scanning calorimetry (DSC), and mass spectrometry (MS), and a microthruster was designed to investigate their combustion characteristics under varying voltages and flow rates. Results reveal the presence of three exothermic peaks in the HAN-based gel propellants at temperatures of 204, 306 °C and 441 °C. The gel propellants experienced violent decomposition between 100 °C and 400 °C, producing low-molecular-weight organics such as C<sub>3</sub>H<sub>8</sub>, C<sub>2</sub>H<sub>6</sub>, H<sub>2</sub>O, O<sub>2</sub>, and NH<sub>3</sub>. For the initial ignition, the flow rate exerts a greater effect of reducing the delay time than the voltage. The reignition exhibited a shorter delay time than the initial ignition, and increasing voltage led to a more significant decrease in the reignition delay time than increasing the flow rate. Under a gelling agent content of approximately 4 wt%, the reignition delay time decreased from 2.35 s to 0.65 s as the voltage increased from 150 V to 250 V, with the flame length and light intensity during the reignition greater than those in the initial ignition. At the end of combustion, the extinguishment delay time changed insignificantly under high voltage. As revealed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses, residues with numerous cavities emerged due to incomplete combustion and the severe agglomeration of the gel propellants, exhibiting a maximum chlorine content of up to 77.73%.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140398993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new sulfur-containing laser-sensitive primary explosive based on thiazole-4-carbohydrazide","authors":"","doi":"10.1016/j.enmf.2024.02.005","DOIUrl":"10.1016/j.enmf.2024.02.005","url":null,"abstract":"<div><div>This study effectively synthesized thiazole-4-carbohydrazide (SZCA) and its ionic salt SZCA·HClO<sub>4</sub> and energetic complex Cu(SZCA)<sub>2</sub>(ClO<sub>4</sub>)<sub>2</sub> (<strong>ECC-1</strong>). The new compound SZCA, SZCA·HClO<sub>4</sub> and <strong>ECC-1</strong> were fully characterized through elemental analysis, infrared spectroscopy, <sup>13</sup>C NMR spectroscopy and thermal stability analysis. The combustion heat of <strong>ECC-1</strong> was measured by oxygen bomb calorimetry, and its detonation performance was predicted by Kamlet-Jacobs formula and EXPLO5, respectively. The mechanical sensitivity of <strong>ECC-1</strong> was tested using BAM method. In particular, we comprehensively evaluated the initiation ability of <strong>ECC-1</strong> through lead plate destruction experiment and laser initiation experiment. The results show that <strong>ECC-1</strong> have a decomposition temperature of 236 °C, exhibits acceptable mechanical sensitivity (impact sensitivity: 3.4 J, friction sensitivity: 4 N), and decent detonation properties (<em>D</em>: 6.6 km s<sup>−1</sup>, <em>P</em>: 21.3 GPa). And <strong>ECC-1</strong> could be initiated by a single-pulse laser (λ: 808 nm, <em>P</em>: 20 W, <em>t</em>: 3 ms), and successfully detonated the next charge, such as RDX and CL-20.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139886297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tensors of thermal deformation for various polymorphic modifications of 2,4-dinitroanisole","authors":"","doi":"10.1016/j.enmf.2024.02.002","DOIUrl":"10.1016/j.enmf.2024.02.002","url":null,"abstract":"<div><div>The anisotropic characteristics of thermal deformation of ultrapure 2,4-dinitroanisole (2,4-DNAN) crystals were determined by the methods of powder thermorentgenography of the internal standard. The points of structural changes are registered in increments of 10 K, and in the melting region of 2 and 1 K. Calculations of powder X-ray diffraction data are performed by methods of full-profile analysis with a cycle of quantum modeling of the structure of molecules integrated into the algorithm. The Pauli, Le Bail (WPPD), Rietveld (WPPF) and WPPM methods were used as reference methods for full-profile analysis. The main crystallographic axes and characteristic surfaces of the thermal deformation tensor α and β-2,4-DNAN are determined. At atmospheric pressure, the main coefficients of linear (<em>α</em>) and volumetric (<em>β</em>) thermal deformation (expansion) were at 293 K for <em>α</em>-2,4-DNAN with <em>α</em><sub><em>1</em></sub>(293) = 11,516 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub>2</sub>(293) = −0,120 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub><em>3</em></sub>(293) = 5,098 × 10<sup>−5</sup> K<sup>−1</sup>, <em>β</em>(293) = 16,333 × 10<sup>−5</sup> K<sup>−1</sup>; at 293 K for <em>β</em>-2,4-DNAN with <em>α</em><sub><em>1</em></sub>(293) = 13,217 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub><em>2</em></sub>(293) = 0,494 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub>3</sub>(293) = −8,6504 × 10<sup>−5</sup> K<sup>−1</sup>, <em>β</em>(293) = 6,8191 × 10<sup>−5</sup> K<sup>−1</sup>; at 260 K for <em>β′</em>-2,4-DNAN with <em>α</em><sub><em>1</em></sub>(260) = 25,214 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub><em>2</em></sub>(260) = −5,823 × 10<sup>−5</sup> K<sup>−1</sup>, <em>α</em><sub><em>3</em></sub>(260) = 7,741 × 10<sup>−5</sup> K<sup>−1</sup>, <em>β</em>(260) = 27,112 × 10<sup>−5</sup> K<sup>−1</sup>.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139770721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Features of the mechanism of pasty propellants burning","authors":"","doi":"10.1016/j.enmf.2023.10.002","DOIUrl":"10.1016/j.enmf.2023.10.002","url":null,"abstract":"<div><div>The composition of a pasty propellant for small-sized space engines has been proposed. For this propellant, a research of the burning process was carried out. This research included the determination of the burning rate law, the characteristics of the agglomeration process, and the properties of the surface layer. The presence of an intermediate structure, a skeleton layer, during the burning of such propellants, and the nature of the influence of pressure, additives, and the size of oxidizer particles on this structure, have been established. The determining influence of this structure on the burning process is shown. Composition solutions that provide control over the burning rate law of such propellants are determined. These solutions make it possible to change the absolute value of the burning rate, as well as its dependence on pressure. Regularities of the agglomeration process have been established. These regularities are associated with the features of the formation of the skeleton layer, which depend on the structure of the propellant, pressure, and the presence of additives.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135760565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Construction and combustion behavior of horizontal two-dimension combustion networks of boron-metal oxides","authors":"","doi":"10.1016/j.enmf.2024.08.005","DOIUrl":"10.1016/j.enmf.2024.08.005","url":null,"abstract":"<div><div>In order to break through the top-down combustion mode brought by the traditional pillars, it is explored to explore the exploration of delay composition array construction in two-dimensional dimensions. In this study, B-CuO, B-Bi<sub>2</sub>O<sub>3</sub>, B-Fe<sub>2</sub>O<sub>3</sub> sticks and combustion networks with good forming properties were prepared with the help of a micro-pen direct ink writing device by dispersing the above materials in DMF with boron and metal oxides as the main body of the charge and F<sub>2602</sub> as the binder. The sticks were thermally ignited using a nichrome wire, and the flame propagation behaviors of the sticks with different formulations, spacings and heights were tracked with a high-speed camera, and a series of combustion networks were designed on the premise of not leaping into flames. Results show that the B-CuO stick has the fastest ignition speed level (19.71–29.02 mm ·s<sup>−1</sup>) at equivalence ratios of 1.0–4.0, followed by B-Bi<sub>2</sub>O<sub>3</sub> (5.99–16.01 mm ·s<sup>−1</sup>) and B-Fe<sub>2</sub>O<sub>3</sub> is the slowest (1.91–4.94 mm ·s<sup>−1</sup>). The sticks burned best at an equivalence ratio of 1.0–1.5. A variety of combustion networks were constructed on 50 × 50 mm glass slides by selecting B-CuO, B-Bi<sub>2</sub>O<sub>3</sub>, and B-Fe<sub>2</sub>O<sub>3</sub> at the equivalence ratios of 1.0, 1.5, and 1.5, respectively, among which B-CuO had the shortest combustion time (5.17 s), the shortest total combustion network length (252 mm), and 400 mm network could be realized for B-Bi<sub>2</sub>O<sub>3</sub>. Construction and 19.85 s, and B-Fe<sub>2</sub>O<sub>3</sub> can realize 608 mm network length and 130.7 s combustion time. Through these studies, the two-dimensional combustion network construction of boron-metal oxides was realized, which provides a new idea for the delay action in small size.</div></div>","PeriodicalId":34595,"journal":{"name":"Energetic Materials Frontiers","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142263724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}