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1.
Alkyl‐substituted ferrocene‐based burning rate catalysts exhibit high migration and volatility during curing process and prolonged storage of the composite solid propellants. To deal with the drawbacks twenty‐one dinuclear (ferrocenylmethyl)imidazolium compounds paired with polycyano anions, were synthesized and characterized by 1H NMR, 13C NMR, UV/Vis, elementary analysis, and both 2 and 11 were further characterized by single‐crystal X‐ray diffraction. The migration test revealed that the compounds have excellent anti‐migration ability. The cyclic‐voltammetry results suggested that they are quasi‐reversible or irreversible redox systems. The TG/DSC analyses showed that the compounds are highly thermal stable. Their effects on the thermal decomposition of ammonium perchlorate (AP) and 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX) were additionally examined. The results showed that the new compounds have strong effects on the thermal decomposition of both AP and RDX during combustion. Both 13 and 21 are more excellent than catocene for increasing the released heats of AP and can be used as alternatives of catocene in the composite solid propellants.  相似文献   

2.
Ferrocenyl ionic compounds, consisting of the 5‐ferrocenyltetrazolate anion and a guanidinium or a 1‐alkyl‐3‐methylimidazolium cation, were synthesized and characterized by 1H NMR, 13C NMR, and UV/Vis spectroscopy, as well as elementary analysis. The molecular structures of four compounds were additionally confirmed by single‐crystal X‐ray diffraction. Results of the TG and DSC analyses showed that some compounds display high thermal stability. Cyclic voltammetry investigations suggested that the compounds exhibit redox waves for the ferrocenyl groups and are considered as irreversible redox systems. Migration studies revealed that migration trends of the compounds are much lower than that of 2, 2‐bis(ethylferrocenyl)propane (Catocene), extensively used in composite solid propellants. Their catalytic performances for thermal decomposition of ammonium perchlorate (AP), 1, 3,5‐trinitro‐1, 3,5‐triazacyclohexane (RDX), and 1, 2,5, 7‐tetranitro‐1, 3,5, 7‐tetraazacyclooctane (HMX) were evaluated by DSC and/or TG techniques. Most of the compounds exhibit high catalytic efficiency in the thermal degradation of AP and RDX. Those of the guanidine‐containing compounds 1 – 3 are better, implying that nitrogen‐rich moieties are beneficial to enhancing released heats of some energetic materials. These guanidine salts could be used as ferrocene‐based burning rate catalyst candidates in composite solid propellants.  相似文献   

3.
Alkylferrocene‐based burning‐rate catalysts (BRCs) show conspicuous migration tendency and volatility during prolonged storage and fabrication process of a composite solid propellant. To enhance anti‐migration ability of the BRCs, forty novel ionic coordination compounds, [M(L)4(H2O)2]mXn (M = Mn2+, Co2+, Cu2+, Ni2+, Zn2+, Fe2+, Pb2+, Cr3+, Bi3+, or Cd2+; L = ferrocenylmethyl imidazole or ferrocenylmethyl‐1,2,4‐triazole; X = picrate or trinitroresorcinolate), were synthesized and characterized by FT‐IR, UV/Vis, and elementary analysis. Additionally, the crystal structures of six compounds were confirmed by single‐crystal X‐ray diffraction. The TG analyses revealed that the new compounds show high thermal stability. Cyclic voltammetry studies suggested that theyare irreversible redox systems. Their catalytic activities in the thermal degradation of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclo‐hexane (RDX) and 1,2,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane (HMX) were examined by DSC technique. The results indicated that all the new compounds exert great effects on the thermal decomposition of AP and RDX, among them some compounds are more active than catocene. Compound 26 has good catalytic ability in the thermal decomposition of HMX, representing a rare example of the reported ferrocene‐based BRCs which show catalytic activity during combustion of HMX.  相似文献   

4.
Alkylferrocene‐based burning rate catalysts exhibit high migration tendency and volatility during prolonged storage and fabrication process of the solid propellants. To retard the migration problems, eight ionic compounds composed of ferrocenylmethyldimethylammonium cation paired with a common energetic anion, were synthesized by “one‐step” procedure. The compounds were characterized by FT‐IR, NMR, and UV/Vis spectroscopy as well as elementary analysis. Their crystal structures were confirmed by single‐crystal X‐ray diffraction. The TG and DSC analyses indicated that they exhibit high thermal stability. Cyclic voltammetry studies suggested that most of them show reversible or quasi‐reversible redox waves. The anti‐migration results revealed that 1 – 4 are low‐migratory compounds, but 5 exhibits high migration trends. The TG curves at 70 °C for 24 h showed that all of them have low volatility. They have from high to low impact sensitivity depending on the anions of the compounds. They all exhibit significant effect on the thermal decomposition of ammonium perchlorate (AP) and some of them accelerate the thermal degradation of 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX). Among them 4 is the best one. Unexpectedly, compound 5 , with 1H‐tetrazolate as anion, can decompose into its original reactants at the temperature just higher than its melting point and could show smart‐material functionality in solid propellants.  相似文献   

5.
Alkylferrocene‐based burning‐rate catalysts (BRCs) exhibit distinct migration tendency and high volatility and thus result in inferior performance of composite solid propellants during their combustion processes. To deal with these drawbacks, a novel dinuclear nitrogen‐rich ferrocene derivative, 4‐amino‐3,5‐bis(4‐ferrocenyl‐1,2,3‐triazolyl‐1‐methyl)‐1,2,4‐triazole (BFcTAZ) and its twenty seven ionic coordination compounds, [M2(BFcTAZ)2(H2O)4]mXn·xH2O (M = Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Pb2; X = polycyano anions), were synthesized and characterized by FT‐IR, UV/Vis, and elementary analysis. Crystal structure of BFcTAZ was further confirmed by single‐crystal X‐ray diffraction and a general molecular structure of the new complexes was proposed. Their high thermal stability was verified by TG technique. Cyclic voltammetry studies suggested that the new compounds are diverse redox systems. Their effects on the thermal degradation of some common oxidizers were measured by DSC technique. The results indicated that most of the new complexes exert great effects on the thermal decomposition of AP, RDX, and 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7) and some of them are more active than catocene. The Cu2+ complexes are among the excellent ones. However, only six compounds have appreciable catalytic activity in the thermal degradation of HMX.  相似文献   

6.
Eighteen ionic polyferrocenyl compounds with 5‐ferrocenyl‐1H‐tetrazolate as anion and mono‐ and dinuclear ferrocenyl‐alkylammonium as cations were synthesized and characterized by 1H NMR, 13C NMR, FT‐IR, and UV/Vis spectroscopy, and elemental analysis. Molecular structures of three compounds were further confirmed by single‐crystal X‐ray diffraction. Their thermal stability was evaluated by TG and DSC and found that they are of high thermal stability. The cyclic voltammetry analysis suggested that each of the compounds exhibits only an irreversible redox wave of the ferrocene units in the molecule. Both migration and volatility test results showed that, on comparison with those of Catocene, all tested compounds exhibit much more excellent anti‐migration ability and most of the tested compounds have lower volatility. Their effects on the thermal disintegration of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), and 1,2,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane (HMX) were measured by DSC. The results revealed that most of the compounds exhibit significant catalytic effects on the thermal degradation of AP and RDX. Particularly, most of the compounds containing one ferrocene unit in their cations show higher activity than that of Catocene. These compounds can be used as alternatives to Catocene in the composite solid propellants.  相似文献   

7.
Twenty‐eight novel ferrocenyl ionic compounds, composed of mononuclear 1‐ferrocenylmethylalkyldimethylammoniums, 1‐ferrocenylmethyl‐3‐alkylimidazoliums, or their dinuclear analogs and [Fe(CN)6]3– anion, were designed and synthesized to tackle significant volatility and migration tendency of ferrocene‐based burning rate catalysts (BRCs) used currently in the composite solid propellants. The new compounds were characterized by UV/Vis, FT‐IR, and elementary analysis. The crystal structures of compounds 2· 5H2O and 3· CH2Cl2 · 4H2O verified the successful preparation of the desired ionic compounds. The TG tests at 70 °C for 24 h revealed that the new compounds exhibit lower volatility than catocene. The cyclic‐voltammetry results suggested that new compounds are quasi‐reversible or irreversible redox systems. TheTG/DSC analyses exhibited that the compounds are of highly thermal stability. Their catalytic effects on the thermal degradation of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), and 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazacyclooctane (HMX) were investigated. The results showed that most of the compounds exert great effects on the thermal degradation of AP and RDX during combustion. 11 and 2 are comparable to catocene in the thermal decomposition of AP and RDX, respectively, and can therefore be used as alternatives of catocene in a composite solid propellant. Some new compounds are unexpectedly active in promoting the thermal disintegration of HMX.  相似文献   

8.
Sodium and potassium methyl(nitroso)amide (M[CH3N2O], M = Na ( 1 ), K ( 2 )) were prepared by the reaction of monomethylhydrazine with iso‐pentyl nitrite or n‐butyl nitrite and a suitable metal ethoxide (M[CH3CH2O], M = Na, K) in an ethanol‐ether mixture. The reaction of monomethylhydrazine with a small excess of iso‐pentyl nitrite or n‐butyl nitrite and in the absence of a metal ethoxide led to the formation of N‐nitroso‐N‐methylhydrazine (CH3(NO)N–NH2, ( 3 )). Alternatively, compound 3 was prepared by the amination reaction of 1 or 2 using the sodium salt of HOSA in ethanol solution. Compounds 1–3 were characterized using elemental analysis, differential scanning calorimetry, mass spectrometry, vibrational (infrared and Raman) and UV spectroscopy and multinuclear (1H, 13C and 15N) NMR spectroscopy. For compounds 1–3 , several physical and chemical properties of interest and sensitivity data were measured and for compound 3 thermodynamic and explosive properties are also given. Additionally, the solid‐state structure of compound 3 was determined by single‐crystal X‐ray analysis and the structures of the cis‐ and trans‐[CH3N2O] anions and that of 3 were optimized using DFT calculations and used to calculate the NBO charges.  相似文献   

9.
As a key research objective for environmentally friendly energetic materials, energetic salts without heavy metal have received wide attention. The energetic salts DAG · PA · H2O ( 1 ) and DAG · TNR · H2O ( 2 ) were synthesized by using diamino‐glyoxine (DAG) and picric acid (PA) or 2, 4,6‐trinitro‐resorcinol (TNR) as raw materials, and their structures were characterized by elemental analysis, FT‐IR, 1H NMR, and 13C NMR spectroscopy. Single crystals of the title salts were cultured and their structures were determined by X‐ray single‐crystal diffraction. Both salts belong to the triclinic space group P1 with density values of 1.764 and 1.751 g · cm–3, respectively. The thermal decomposition behaviors of both salts were investigated by differential scanning calorimetry (DSC), the non‐isothermal kinetic parameters and the critical temperature of thermal explosion were calculated. The heats of formation for the salts were also determined through the combustion heats date measured by using the oxygen bomb calorimetry. In addition, the detonation pressure (P) and detonation velocities (D) of the salts were predicted by using the K‐J equations, and their sensitivities towards impact and friction were tested. The results indicated that the title salts have potential applications in the field of energetic materials.  相似文献   

10.
《化学:亚洲杂志》2017,12(3):378-384
In the design of advanced energetic materials, high‐density explosophores play a pivotal role because of their remarkable enhancement of both density and molecular stability. Using diversified functionalization strategies, a comparative study involving various nitropyrazole anions shows that these are crucially important in determining performance and stability. A promising family of pyrazole‐based energetic ionic derivatives were synthesized and characterized by NMR and IR spectroscopies, and elemental analysis. Among them, 7 , 8 , 11 – 13 exhibit favorable overall performance as energetic materials.  相似文献   

11.
首次通过不同阴离子的钾盐和不同的季铵化的咪唑,吡咯溴盐/氯盐进行离子交换,合成了一系列含氰基官能团的阴离子功能化离子液体。通过红外、核磁共振、质谱对离子液体的结构进行表征;通过TGA对离子液体的热稳定性进行测定,结果发现功能化离子液体具有良好的热稳定性,其分解温度在224-289℃范围内。将功能化离子液体[EMIm][N(CN)COC2H5]作为配体应用于无膦配体的Suzuki偶联反应,发现在反应中加入功能化离子液体[EMIm][N(CN)COC2H5]可以使反应收率提高10-20%。  相似文献   

12.
C6F5I(CN)2 and x‐FC6H4I(CN)2 (x = 2, 3, 4) were isolated from reactions of the corresponding aryliodine difluorides ArIF2 and a stoichiometric excess of Me3SiCN in CCl3F (0 °C) or CH2Cl2 (20 °C), respectively. In addition, x‐FC6H4I(CN)2 compounds were synthesized in good yields on alternative routes, namely from 3‐ or 4‐FC6H4I(OC(O)CH3)2 or 4‐FC6H4I(OC(O)CF3)2 or from 4‐FC6H4IO and Me3SiCN in CH2Cl2 at 20 °C. In the 1 : 1 reaction of C6F5IF2 and Me3SiCN a lower temperature was necessary to suppress partial disubstitution and to obtain the first example of a new type of aryliodine(III) cyanide compounds, C6F5I(CN)F. 4‐FC6H4I(CN)F could be isolated from the equimolar reaction of 4‐FC6H4IF2 and Me3SiCN in CH2Cl2 even at 20 °C. The new products were characterized by multi‐NMR and Raman spectroscopy. The molecular structures of C6F5I(CN)2, 3‐ and 4‐FC6H4I(CN)2, C6F5I(CN)F, and 4‐FC6H4I(CN)F are discussed and compared with that of C6F5IF2. The reactivity of C6F5I(CN)F towards fluoride acceptors EFn (BF3, AsF5) and RxEX?x (C6F5SiF3, C6H5SiF3, C6H5PF4, Me3SiCl, Me3SiC6F5) were investigated and showed differing reaction patterns (fluoride abstraction, aryl transfer, chloride transfer). Besides the molecular entities C6F5I(CN)F and C6F5I(CN)Cl, the corresponding iodonium salts [C6F5(CN)I][BF4] and [C6F5(CN)I][AsF6] were isolated. The thermal stability of ArI(CN)2 and ArI(CN)F, neat and in solution, as well as the reactivity of 4‐FC6H4I(CN)2 towards the Lewis acid BF3 are reported.  相似文献   

13.
A series of energetic coordination compounds [Co(tza)2}n ( 1 ), [Bi(tza)3]n ( 2 ), {[Cu4(tza)6(OH)2] · 4H2O}n ( 3 ), [Mn(tza)2]n ( 4 ), {[Bi(tza)(C2O4)(H2O)] · H2O}n ( 5 ) and [Fe3O(tza)6(H2O)3]NO3 ( 6 ) based on tetrazole‐1‐acetic acid (Htza) were synthesized though environmentally friendly methods. The coordination compounds were characterized by elemental analyses, IR spectroscopy, single‐crystal and powder X‐ray diffraction (PXRD), thermogravimetric analyses (TG), and differential scanning calorimetry (DSC). Their catalytic performances and the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 on the thermal decomposition of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) were all investigated by DSC. The results revealed that compounds 1 – 6 are thermally stable energetic compounds and they all exhibit high catalytic action for HMX thermal decomposition. The catalytic effects of the compounds on HMX thermal decomposition are closely related to the oxides, which come from the decomposition of the compounds, but have no positive relationships with the heat releases of the compounds themselves. Moreover, the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 were observed. Their mixtures at different mass ratio have different synergetic catalytic effects, and the sequence of the biggest synergetic index (SI) in each system is copper‐manganese system (compounds 3 and 4 ) > iron‐bismuth system (compounds 5 and 6 ) > cobalt‐bismuth system (compounds 1 and 2 ), indicating that the synergistic catalytic effects are mainly related to the combination and the proportion of the compounds.  相似文献   

14.
The synthesis of 5,5′‐diamino‐3,3′‐azo‐1H‐1,2,4‐triazole ( 3 ) by reaction of 5‐acetylamino‐3‐amino‐1H‐1,2,4‐triazole ( 2 ) with potassium permanganate is described. The application of the very straightforward and efficient acetyl protection of 3,5‐diamino‐1H‐1,2,4‐triazole allows selective reactions of the remaining free amino group to form the azo‐functionality. Compound 3 is used as starting material for the synthesis of 5,5′‐dinitrimino‐3,3′‐azo‐1H‐1,2,4‐triazole ( 4 ), which subsequently reacted with organic bases (ammonia, hydrazine, guanidine, aminoguanidine, triaminoguanidine) to form the corresponding nitrogen‐rich triazolate salts ( 5 – 9 ). All substances were fully characterized by IR and Raman as well as multinuclear NMR spectroscopy, mass spectrometry, and differential scanning calorimetry. Selected compounds were additionally characterized by low temperature single‐crystal X‐ray diffraction measurements. The heats of formation of 4 – 9 were calculated by the CBS‐4M method to be 647.7 ( 4 ), 401.2 ( 5 ), 700.4 ( 6 ), 398.4 ( 7 ), 676.5 ( 8 ), and 1089.2 ( 9 ) kJ · mol–1. With these values as well as the experimentally determined densities several detonation parameters were calculated using both computer codes EXPLO5.03 and EXPLO5.04. In addition, the sensitivities of 5 – 9 were determined by the BAM drophammer and friction tester as well as a small scale electrical discharge device.  相似文献   

15.
In this work, the treatment of 3,6,7‐triamino‐[1,2,4]triazolo[4,3‐b][1,2,4]triazole (TATOT)[1] with sulfuric acid and sodium nitrite results in elimination of the N‐amine and the formation of the new energetic anion 3,6‐dinitro‐[1,2,4]triazolo[4,3‐b][1,2,4]triazolate (DNTT) via nitro‐Sandmeyer chemistry. This new energetic anion is available in a convenient and inexpensive three‐step process from inexpensive commercial starting materials. Several nitrogen rich salts of this material have been prepared and their chemical (infrared, Raman, NMR, single‐crystal X‐ray) and energetic (impact, friction, thermal) properties determined. As a rule, this class of energetic salts are insensitive energetic materials.  相似文献   

16.
CO2‐binding organic liquids (CO2BOLs) are mixtures of a base (typically an amidine or guanidine) and an alcohol, and have been shown to reversibly capture and release CO2 with low reaction energies and high gravimetric CO2 capacity. We now report the ability of such liquid blends to chemically bind and release other acid gases such as CS2, COS, and SO2 analogously to CO2. These systems bind with sulfur‐containing acid gases to form colored ionic liquids with new O‐alkylxanthate, O‐alkylthiocarbonyl, and O‐alkylsulfite anions. The capture and thermal stripping of each acid gas from these systems and their applicability towards flue gas desulfurization is discussed.  相似文献   

17.
Energetic salts composed of ureido, furazan, and tetrazole were prepared by simple and efficient chemical routes to explore new insensitive and thermostable energetic materials. 3‐Ureido‐4‐tetrazole‐furazan ( 3 ) and its ammonium salt ( 5 ) and hydrazinium salt ( 6 ) were confirmed by single‐crystal X‐ray diffraction. The thermal stabilities of the synthesized salts were studied using differential scanning calorimetry, and the detonation performances of these salts were calculated using EXPLO 5 V6.01. All the salts exhibit good thermal stability (Td: 148–259 °C) and mechanical sensitivities (IS > 40 J, FS > 360 N), and their detonation velocities range from 7316 to 8655 m · s–1. Compounds 6 and 10 are potential candidates as novel insensitive and heat‐resistant explosives because of their high detonation temperatures of 247 and 256 °C, good detonation velocities of 8432 and 8523 m · s–1, and good detonation pressures of 25.6 and 26.8 GPa.  相似文献   

18.
Nitrogen‐rich 3, 4‐bis(1H‐tetrazol‐5‐yl)furoxan (H2BTF, 2 ) and its energetic salts with excellent thermal stability were successfully synthesized and fully characterized by 1H, and 13C NMR, and IR spectroscopy, differential scanning calorimetry (DSC), and elemental analyses. Additionally, the structures of barium ( 3 ) and 1‐methyl‐3, 4, 5‐triamino‐triazolium ( 10 ) salts were confirmed by single‐crystal X‐ray diffraction. The densities of the energetic salts paired with organic cations range between 1.56 and 1.85 g · cm–3 as measured by a gas pycnometer. Based on the measured densities and calculated heats of formation, the detonation pressures and velocities are calculated to be in the range 23.4–32.0 GPa and 7939–8915 m · s–1, which make them competitive energetic materials.  相似文献   

19.
Energetic salts of en · PA · H2O and en · TNR were synthesized by using ethylenediamine and picric acid (PA) or 2,4,6‐trinitroresorcinol (TNR) as raw materials, and their structures were characterized by elemental analysis and FT‐IR spectroscopy. Single crystals of the title salts were obtained and their structures were determined by single‐crystal X‐ray diffraction. The thermal decomposition behaviors were investigated by DSC and TG‐DTG technologies, furthermore the non‐isothermal kinetic parameters and enthalpies of formation for the salts were calculated. Their combustion heats were measured by oxygen bomb calorimetry and their enthalpies of formation were also calculated based on the combustion heat data. In addition, the detonation pressure (P) and detonation velocities (D) of the salts were predicted by using the K‐J equations. The results indicated that the title salts have potential applications in the field of energetic materials.  相似文献   

20.
The energetic complex, [Co(2,4,3‐tpt)2(H2O)2] · 2NO3 ( 1 ) [2,4,3‐tpt = 3‐(2‐pyridyl)‐ 4‐(4'‐pyridyl)‐5‐(3′‐pyridyl)‐1H‐1,2,4‐triazole], was synthesized and characterized by single‐crystal X‐ray diffraction, thermogravimetric analyses, elemental analysis, X‐ray powder diffraction, and IR spectroscopy. The title complex is a 0D motif with a unit of [Co(2,4,3‐tpt)2(H2O)2]2+, whereas NO3 ions not only act as counter anions to balance the charge of the CoII cations, but also provide hydrogen bond interactions, which make the 0D motif into a 1D chain. Furthermore, the thermal decomposition of ammonium perchlorate (AP) with complex 1 was explored by differential scanning calorimetry (DSC) over the temperature range from 50–500 °C. AP is completely decomposed in a shorter time in the presence of complex 1 , and the decomposition heat of the mixture is 2.143 kJ g–1, significantly higher than pure AP. By Kissinger's method, the ratio of Ea/ln(A) is 11.87 for the mixture, which indicates that complex 1 shows good catalytic activity toward AP decomposition.  相似文献   

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