CHINESE JOURNAL OF ENERGETIC MATERIALS
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    摘要

    为制备高密度、低粘度、高比冲、宽液态温度范围、热稳定性好的新颖推进剂燃料,以1,2,3‑三唑为原料,在碱作用下与卤代烃发生N‑烷基化反应,并与氯化氢气体成盐酸盐,该盐再与氰基硼氢化钠发生复分解反应,得到一系列新颖三唑氰基硼烷复合物。点火实验表明,该系列复合物可作为液体推进剂燃料。利用傅里叶变换红外光谱(FT‑IR),核磁共振1H NMR13C NMR11B NMR)、高分辨质谱(HRMS)等对其结构进行了表征;分别利用差示扫描量热法(DSC)、排气法密度仪、粘度仪和高速摄影等,测定化合物的热分解温度、密度、粘度和点火延迟时间等性能;运用Gaussian 09软件、密度泛函理论(DFT)B3LYP/6‑31++G(d,p)基组优化化合物结构,并基于此优化结构计算化合物的生成焓,据此运用Explo5 v6.02软件计算其理论比冲。结果表明,1‑丙基三唑氰基硼烷复合物(3)的生成焓为1.5 kJ·g-1,具有最短的点火延迟时间(12 ms),密度1.024 g∙cm-3,熔点低于-70 ℃,热分解起始温度达233 ℃(onset),粘度16 mPa∙s,理论比冲为201.7 s,密度比冲达357 s∙g∙cm-3

    Abstract

    To develop novel hypergolic propellant fuels with high density, low viscosity, wide liquid temperature range, high specific impulse, and high decomposition temperature, a series of N‑alkyltriazole cyanoborane complexes were prepared in a straight forward way by treating N‑substituted triazoles hydrogen chloride salts and NaBH3CN. The synthesized compounds were characterized by IR, NMR and HRMS for their structures, and measured by differential scanning calorimetry (DSC), densimeter and viscometer for their thermostability, density, viscosity and ID. On the other hand, Gaussian 09 was used to optimize the crystal structure and calculate the formation enthalpy, based on which Explo5 v6.02 was employed to predict the theoretical specific impulse. Four out of five compounds were found to be liquid at room temperature and proved to be hypergolic with white fuming nitric acid (WFNA) by the droplet test. Especially, N‑Propyl‑1,2,3‑triazole cyanoborane complex (3) demonstrated attractive properties such as short ID time(12 ms), high density (1.024 g∙cm−3), good thermostability (Td=233 ℃, onset), good Isp (201.7 s) and ρIsp (357 s∙g∙cm−3), super low viscosity (16 mPa∙s) and wide liquid range (Tm<-70 ℃), showing the promising application potential as a propellant fuel candidate.

  • 1 引 言

    1

    液体推进剂具有点火延迟短,可重复点火等优点,被广泛应用于卫星、火箭、导弹等领[1]。其主流推进剂燃料大多属于肼或肼类衍生物,其高挥发性、毒性、致癌性等致使该类燃料在生产、储存、运输、使用过程中存在较大危害,因此,绿色、环保、安全的推进剂燃料成为研究热[2]

    2008年,Schneider[3]首先报道了二氰胺阴离子和咪唑类阳离子组成的离子液体(Ionic Liquids,ILs)的合成,将其与氧化剂白色发烟硝酸(WFNA)接触发生点火燃烧,被称为自燃离子液体(Hypergolic Ionic Liquids, HILs)。此后十余年,越来越多研究者关注此类低挥发性的HILs,相继合成了二氰胺阴离子[3]、硝基氰胺阴离子[4,5]、次磷酸阴离子[6]等HILs,并研究了替换肼类液体推进剂燃料的可能性。但该类HILs也存在一些问题,如有的密度低,有的点火延迟时间(Ignition Delay time,ID)太长如大于30 ms,有的玻璃化转变温度较高即液态温区较窄,有的粘度高等。

    文献表明,含有B—H键的HILs比氰胺类HILs具有更优异的点火延迟时间和较低的粘度,包括[BH2(CN)2]-,[BH3(CN)]-,BH4-,[BH3(CN) BH2(CN)]-[7,8,9,10,11,12,13,14]。陈甫雪[15,16]在含B—H键的分子结构基础上引入四唑基团,既提高了自燃离子液体的正生成焓,又获得了较短的点火延迟时[17]。另外,硼烷及硼烷衍生物的胺类Lewis酸碱加合物也是一类重要液体推进剂燃料,如氨硼烷和联氨硼[18,19],以及张庆华[20]合成的卡宾硼烷络合物,陈甫雪[21]报道的咪唑硼烷复合物。有的硼烷复合物不仅有着优异的点火性能,还表现出了良好的水稳定性。硼烷复合物的合成原料易得,价格较低,工艺路线简单,合成过程中不使用金属化合物,具有较好的工艺开发前景。

    为获得点火延迟时间短、密度高、粘度低、液态温度区间宽、热稳定好、以及高比冲的液体推进剂燃料,本研究选用氮含量较高的1,2,3‑三唑为底物,具有较高密度的氰硼烷为配体,设计并合成了一系列自燃型氰基硼烷三唑复合物,表征了其结构,考察了密度、粘度、热性能等,测试了部分复合物的点火性能,并用量子力学的方法预估了目标化合物的生成焓和比冲。

  • 2 实验部分

    2
  • 2.1 试剂与仪器

    2.1

    药品及试剂:1,2,3‑三唑,碘甲烷,碘乙烷,1‑碘丙烷,1‑碘丁烷,烯丙基溴,浓硫酸,氯化钠,碳酸钾,乙腈,四氢呋喃,分析纯,均购于安耐吉和Alfa‑Aesar公司。

    仪器: Bruker 400/700 AVANCE spectrometer核磁共振仪;IRAffinity‑1s(KBr压片)红外光谱仪;Bruker Apex IV FTMS高分辨质谱;岛津DSC‑60差示扫描量热仪;Fastcam SA4高速摄像机;TA DHR‑2流变仪;Micromeritics Accupyc Ⅱ 1340密度仪。

  • 2.2 实验过程

    2.2

    参考并改进文献[22-23]方法:改用1,2,3‑三唑为原料、碱性较弱的碳酸钾做碱,室温下在乙腈溶剂中与卤代烃反应,合成烷基化三唑前体。接着,向该前体的甲醇溶液中通入氯化氢气体生成相应盐酸盐,该盐与氰基硼氢化钠在四氢呋喃溶液中回流反应,粗产物经柱层析分离,得到系列纯的氰硼烷三唑复合物,合成路线如Scheme 1。

    Scheme 1 Synthetic route of N‑alkytriazole‑cyanoborane

  • 2.2.1 化合物1的合成

    2.2.1

    将1,2,3‑三唑(10.0 g, 144.8 mmol),乙腈(50 mL)置于100 mL的两口烧瓶中,搅拌下加入碳酸钾(24.0 g, 174.0 mmol),室温搅拌1 h,然后缓慢滴加碘甲烷(22.6 g, 159.2 mmol)。滴毕,继续室温搅拌,过夜。过滤,旋干溶剂,得到5.660 g粗品。粗品溶于甲醇(100 mL),通入氯化氢气体,搅拌6 h。过滤,旋干溶剂。粗品经硅胶柱层析纯化,得到白色固体7.740 g。取7.7 g产品,与氰基硼氢化钠(4.500 g, 71.5 mmol)一起加入到250 mL烧瓶中,加入四氢呋喃(80 mL),搅拌,回流反应12 h。反应结束后,旋干溶剂。粗品硅胶柱层析分离(V石油醚V乙酸乙酯=1∶2),回收N‑甲基‑1,2,3‑三唑2.774 g(回收率50.8%),得白色固体产品0.998 g,折合收率25.0%。

    1H NMR (400 MHz, CDCl3)δ: 7.09 (s, 1H, CH), 7.02 (s, 1H, CH), 4.28 (s, 3H, CH3), 3.10~2.10 (m, 2H, BH2CN). 13C NMR (100 MHz, CDCl3)δ: 133.0, 128.1, 39.1. 11B (128 MHz, CDCl3)δ: -21.52 (t, J=103.8 Hz). IR (KBr, ν/cm-1):3157, 3140, 2968, 2425, 2199, 1527, 1269, 1184, 1119, 1093. HRMS (ESI) m/z, [M+H]+ calcd for C4H8BN4: 123.0837; found: 123.0824。

  • 2.2.2 化合物2的合成

    2.2.2

    将1,2,3‑三唑(5.0 g, 72.4 mmol),乙腈(30 mL)置于100 mL的两口烧瓶中,搅拌下加入碳酸钾(12.0 g, 86.9 mmol),室温搅拌1 h,然后缓慢滴加碘乙烷(12.4 g, 79.6 mmol)。滴毕,室温继续搅拌,过夜。过滤,旋干溶剂,得5.630 g粗品。粗品溶于甲醇(100 mL),通入氯化氢气体,搅拌6 h,过滤,旋干溶剂,粗品经硅胶垫过滤,得7.700 g产品,不经柱层析纯化直接与氰基硼氢化钠(3.644 g, 58 mmol)一起加入100 mL烧瓶中,加入四氢呋喃(50 mL),回流反应12 h。反应结束后,旋干溶剂,粗品硅胶柱层析分离(V石油醚V乙酸乙酯=2∶3),得到淡黄色液体3.133 g,收率39.9%。

    1H NMR (400 MHz, CDCl3)δ: 7.88 (s, 1H, CH), 7.82 (s, 1H, CH), 4.49 (q, J=7.2 Hz, 2H, CH2), 3.20~2.10 (m, 2H, BH2CN), 1.61(t, J=7.6 Hz, 3H, CH3). 13C NMR (100 MHz, CDCl3)δ: 132.8, 126.7, 48.1, 14.9. 11B (128 MHz, CDCl3)δ: −21.22. IR (KBr, ν/cm-1):3144, 2990, 2418, 2201, 1721, 1179, 1119, 1094. HRMS (ESI) m/z, [M+H]+ calcd for C5H10BN4: 137.0993; found: 137.0988。

  • 2.2.3 化合物3的合成

    2.2.3

    将1,2,3‑三唑(2.0 g, 29.0 mmol),乙腈(20 mL)置于100 mL的两口烧瓶中,搅拌下加入碳酸钾(4.8 g, 35.0 mmol),室温搅拌1 h,然后缓慢滴加碘丙烷(7.4 g, 44 mmol)。滴毕,室温继续搅拌,过夜。过滤,旋干溶剂,得1.588 g粗品。粗品溶于甲醇(100 mL),通入氯化氢气体,搅拌反应6 h。过滤,旋干溶剂,粗品经硅胶垫过滤,得2.095 g产品,不经柱层析纯化直接与氰基硼氢化钠(1.093 g, 17.4 mmol)一起加入100 mL烧瓶中,加入四氢呋喃(30 mL),搅拌回流反应12 h。反应结束后,旋干溶剂。粗品硅胶柱层析纯化(V石油醚V乙酸乙酯=1∶1),得淡黄色液体0.932 g,收率43.7%。

    1H NMR (400 MHz, CDCl3)δ: 7.93 (s, 1H, CH), 7.88 (s, 1H, CH), 4.44 (t, J=7.2 Hz, 2H, CH2), 3.36~2.25(m, 2H, BH2CN), 1.95~2.10 (m, 2H, CH2), 1.00 (t, J=7.2 Hz, 3H, CH3). 13C NMR (100 MHz, CDCl3)δ: 132.8, 126.7, 54.4, 23.2, 10.8. 11B (128 MHz, CDCl3)δ: −21.04(t, J=97.7 Hz). IR (KBr, ν/cm-1):3144, 2972, 2417, 2201, 1462, 1177, 1117, 1094. HRMS (ESI) m/z, [M+H]+ calcd for C6H12BN4: 151.1150; found: 151.1141。

  • 2.2.4 化合物4的合成

    2.2.4

    将1,2,3‑三唑(2.0 g, 29.0 mmol),乙腈(30 mL)置于100 mL的两口烧瓶中,搅拌下加入碳酸钾(4.8 g, 35.0 mmol, 1.2 eq),室温搅拌1 h,然后缓慢滴加碘丁烷(9.0 g, 44.0 mmol)。滴毕,室温继续搅拌,过夜。过滤,旋干溶剂,得1.804 g粗品。粗品溶于甲醇(100 mL)当中,通入氯化氢气体,搅拌6 h。过滤,旋干溶剂,粗品经硅胶垫过滤,得2.303 g产品,不经柱层析纯化直接与氰基硼氢化钠(1.087 g, 17.3 mmol)一起加入100 mL烧瓶中,加入四氢呋喃(30 mL),搅拌回流反应12 h。反应结束后,旋干溶剂,粗品经硅胶柱层析纯化(V石油醚V乙酸乙酯=1∶1),得淡黄色液体0.983 g,收率42.0%。

    1H NMR (400 MHz, CDCl3)δ: 8.11 (s, 1H, CH), 7.93 (s, 1H, CH), 4.53 (s, J=7.6 Hz, 2H, CH2), 3.30~2.20 (m, 2H, BH2CN), 2.05~1.93 (m, 2H, CH2), 1.50~1.33 (m, 2H, CH2), 0.98 (t, J=7.6 Hz, 3H, CH3). 13C NMR (175 MHz, CDCl3)δ: 133.2,127.3, 52.6, 31.5, 19.4, 13.2. 11B(128 MHz, CDCl3)δ: −21.34. IR (KBr, ν/cm-1):3142, 2963, 2417, 2199, 1721, 1522, 1466, 1175, 1119, 1092. HRMS (ESI) m/z, [M+H]+ calcd for C7H14BN4: 165.1306; found: 165.1295。

  • 2.2.5 化合物5的合成

    2.2.5

    将1,2,3‑三唑(2.0 g, 29 mmol),乙腈(30 mL)置于100 mL的两口烧瓶中,搅拌下加入碳酸钾(4.8 g, 35.0 mmol),室温搅拌1 h,然后缓慢滴加烯丙基溴(3.0 g, 32.0 mmol)。滴毕,继续室温搅拌,过夜。过滤,旋干溶剂,得1.300 g粗品。粗品溶于甲醇(100 mL),通入氯化氢气体,搅拌6 h。过滤,旋干溶剂,粗品经硅胶垫过滤,得1.697 g产品,不经柱层析纯化直接与氰基硼氢化钠(0.905 g, 14.4 mmol)一起加入100 mL烧瓶中,加入四氢呋喃(30 mL),回流反应12 h。反应结束后,旋干溶剂,粗品经硅胶柱层析纯化(V石油醚V乙酸乙酯=1∶1),得淡黄色液体0.472 g,收率27.3%。

    1H NMR(400 MHz, CDCl3)δ: 7.99(s, 1H, CH), 7.88 (s, 1H, CH), 5.99 (ddt, J=16.8, 10.0, 6.4 Hz, 1H, CH), 5.45 (d, J=10.0 Hz, 1H, CH), 5.43(d, J=17.2 Hz, 1H, CH), 5.06(d,J=6.4 Hz, 2H, CH2), 3.20-2.05(m, 2H, BH2CN). 13C NMR (100 MHz, CDCl3)δ: 133.0, 128.7, 127.2, 123.2, 54.9. 11B (128 MHz, CDCl3)δ: −21.24. IR (KBr, ν/cm-1):3145, 2961, 2417, 2201, 1728, 1165, 1117, 1092. HRMS (ESI) m/z, [M+H]+ calcd for C6H10BN4: 149.0993; found: 149.0991。

  • 3 结果与讨论

    3
  • 3.1 热稳定性

    3.1

    液体推进剂的热性能包括玻璃化温度Tg、熔点Tm、热分解温度Td等。其中,熔点或玻璃化温度越低、热分解温度越高,即液态温区宽,越有利于液体推进剂的储存、转运和使用。在室温下,化合物2~5呈液体状,化合物1呈固体,熔点50 ℃,可能是三唑N原子相连的甲基体积较小引起。利用DSC对化合物1~5的热分解温度进行考察,方法:5 ℃∙min-1升温速率,升温范围化合物1为30~350 ℃,化合物2~5为−70~350 ℃。如表1所示,除化合物5以外,其余化合物的分解温度均在200 ℃以上,热稳定性良好。化合物4有着最高的起始热分解温度,达到了256 ℃。化合物5存在二次分解现象,热分解起始温度分别为157 ℃和204 ℃。相比于偏二甲肼(UDMH,Tg=−57 ℃,沸点为64 ℃),化合物3的分解温度达233 ℃,−70 ℃未观察到凝固点,因此,化合物3被用为推进剂燃料时有较宽的液体范围。

    表1 三唑硼烷复合物的物化性质

    Table 1 Physicochemical properties of N‑alkytriazole cyanoborane adducts

    compoundTgTm)/ ℃Td / ℃ρ / g∙cm-3η / mPa∙sΔHf / kJ∙g-1Ιsp / sρIsp / s∙g∙cm-3ID / ms
    1/ 502251.086-2.3221.735913
    2-42 / 222001.05170.01.8209.635390
    3/ <-702331.02416.01.5201.735712
    4/ <-702561.00232.51.2195.435523
    5/ <-70157 / 2041.06010.12.4214.935533
    UDMH[24]-57-0.790.490.81313.5-4.8
    表1
                    三唑硼烷复合物的物化性质

    Tg is glass‑transition temperature. Tm is melt point (DSC, 5 ℃∙min-1). Td is decomposition temperature (onset, DSC, 5 ℃∙min-1). ρ is experimental density at 25 ℃. η is Viscosity at 25 ℃. ΔHf is heat of formation (Gaussian 09, MP2(full)/6‑311++G(d,p)). Ιsp is specific impulse (Explo5 v6.02, oxidizer N2O4 (equivalence ratio=1.0), isobaric conditions, equilibrium expansion, 7.0 MPa chamber pressure). ρIsp is density specific impulse. ID is ignition delay time.

  • 3.2 黏度及密度

    3.2

    对于液体推进剂而言,密度较高的燃料代表着相等体积的燃料箱可以有着更高的携载能力和推进能力。通过排气法、比重瓶法密度测试,5种三唑硼烷复合物的密度均大于1.00 g∙cm-3,远高于偏二甲肼(0.79 g∙cm-3)。其中,化合物5的密度最高,达到1.060 g∙cm-3,密度最小的化合物4也达到1.002 g∙cm-3。另一方面,液体推进剂粘度越小,在实际应用时越有利于燃料的运输和燃烧传质过程。在25 ℃,化合物2~5的粘度差异较大,化合物2的粘度最大,达到了70 mPa∙s。化合物3和5都表现出了较低的粘度,其中,化合物5的粘度最小10 mPa∙s,化合物3的粘度稍高为16 mPa∙s。

  • 3.3 点火延迟

    3.3

    点火延迟测试通常由从高处自由落体的燃料样品滴向烧杯中的白色发烟硝酸(WFNA),并用高速摄影机(1000 fps)记录点火过程。化合物3的滴落测试结果如图1。当化合物3的液滴接触到白色发烟硝酸表面时开始记录,发生飞溅及剧烈的化学反应并产生易燃性小分子气体,释放热量,局部温度升高,当温度达到燃点时,气体就会被点[17]。从图1可以看出t=12 ms时,化合物3有小火星冒出;t=13 ms时,火焰明亮;t=200 ms时,整个画面呈亮白色,燃烧稳定充分;t=320 ms时,仍在稳定燃烧。从整个点火过程来看,丙基三唑硼烷化合物的点火时间较短,燃烧时间长,能量高,有可能开发成为一种新型的液体燃料。

    图1
                            化合物3与WFNA的滴落实验高速摄影照片

    图1 化合物3与WFNA的滴落实验高速摄影照片

    Fig.1 High‑speed camera photos that show a spatially resolved ignition event for a droplet of 3 falling into WFNA

    其他4个化合物的点火延迟时间,见表1。其中化合物1由于是固体,测试方法是将白色发烟硝酸滴入化合物1中,其他3个化合物测试方法与化合物3相同。

  • 3.4 生成焓及比冲

    3.4

    生成焓采用Gaussian 09软[25]计算。首先,采用B3LYP的方法,选用6‑31++G(d,p)基组对化合物进行结构优化和频率分析,对势能面上能量进行最小优化,经振动分析无虚频,得到稳定几何构型。然后在此基础上,选用MP2(full)/6‑311++G(d,p)基组,计算其单点能量,由此设计等键等电子反应以计算标准摩尔生成焓(HOF),如Scheme 2。

    在298 K的标准生成焓如式(1)所示。

    ΔH298 K=ΣΔHf,P-ΣΔHf,R (1)

    式中,ΔHf,P和ΔHf,R分别表示在298 K时生成物和反应物的标准生成焓,kJ∙mol-1

    等键反应中所涉及的NH3、CH3NH2等烷基胺和1,2,3‑三唑标准生成[26]有详细实验值,但缺少NH3—BH2CN的数值,可通过如式(2)所示的原子化反应经G2计算其标准生成焓。

    CaHbNcaC(g)+bH(g)+cN(g) (2)

    经计算,NH3—BH2CN的ΔHf为1.1 kJ∙mol-1,并由此计算得到该系列三唑硼烷复合物的生成焓。化合物5的标准生成焓最高,达到了2.4 kJ∙g-1;综合性能最好的化合物3也达到了1.5 kJ∙g-1,都远高于偏二甲肼(0.81 kJ∙g-1)。

    基于化合物的标准生成焓计算值和实测密度,利用Explo5 v6.02预估了化合物1~5的比冲,见表1。化合物3的理论比冲最高为201.7 s,密度比冲则达到了357 s∙g∙cm-3

    Scheme 2 Isodesmic reactions for the HOFs calculation of N‑alkytriazole‑cyanoborane compounds

  • 4 结 论

    4

    (1)以1,2,3‑三唑为原料,与卤代烃生成N‑取代三唑,再通入氯化氢气体制备盐酸盐前体,然后与氰基硼氢化钠反应,分别以25.0%~43.7%的不同收率得到一系列三唑氰硼烷复合物,并对目标化合物进行了结构表征。化合物合成工艺简单,原料来源广泛,有望进行实际应用。

    (2)使用Gaussian 09和Explo5 v6.02软件包等对目标化合物的推进剂性能进行了理论预估,化合物3具有最佳的综合性能,熔点温度低于-70 ℃,热分解温度达到了233 ℃(onset),室温粘度16 mPa∙s,密度为1.024 g∙cm-3,标准生成焓达到1.5 kJ∙g-1,密度比冲达357 s∙g∙cm-3,点火延迟时间为12 ms。化合物3可用作液体推进剂的候选燃料。

  • 参考文献

    • 1

      李亚裕.液体推进剂[M]. 北京:中国宇航出版社, 2011: 1.

      LI Ya‑yu.Liquid propellant[M]. Beijing: China Astronautic Publishing House, 2011: 1.

    • 2

      田均均,张庆华.含能离子液体‑新型离子炸药和绿色推进剂燃料[J]. 含能材料, 2014, 22(5): 580-581.

      TIAN Jun‑jun, ZHANG Qing‑hua. Energetic ionic liquid‑new explosives and green propellant fuels[J]. Chinese Journal of Energetic Materials(Hanneng Cailiao), 2014, 22(5): 580-581.

    • 3

      Schneider S, Hawkins T, Rosander M, et al. Ionic liquids as hypergolic fuels[J]. Energy & Fuels, 2008, 22(4): 2871-2872.

    • 4

      HE Ling, TAO Guo‑hong, Shreeve J M, et al. Nitrocyanamide‑based ionic liquids and their potential applications as hypergolic fuels[J]. Chemistry‑A European Journal, 2010, 16(19): 5736-5743.

    • 5

      Joo Y H, GAO Hai‑xiang, Shreeve J M, et al. Inorganic or organic azide‑containing hypergolic ionic liquids[J]. Inorganic Chemistry, 2010, 49(5): 3282-3288.

    • 6

      Maciejewski J P, GAO Hai‑xiang, Shreeve J M. Synthetic methods for preparing ionic liquids containing hypophosphite and carbon‑extended dicyanamide anions[J]. Chemistry‑A European Journal, 2013, 19(9): 2947-2950.

    • 7

      ZHANG Yan‑qiang, GAO Hai‑xiang, Shreeve J M, et al. Ionic liquids as hypergolic fuels[J]. Angewandte Chemie International Edition, 2011, 50(41): 9554-9562.

    • 8

      LI Song‑qing, GAO Hai‑xiang, Shreeve J M. Borohydride ionic liquids and borane/ionic‑liquid solutions as hypergolic fuels with superior low ignition‑delay times[J]. Angewandte Chemie International Edition, 2014, 53(11): 2969-2972.

    • 9

      ZHANG Qing‑hua, YIN Ping, Shreeve J M, et al. Cyanoborohydride‑based ionic liquids as green aerospace bipropellant fuels[J]. Chemistry‑A European Journal, 2014, 20(23): 6909-6914.

    • 10

      LIU Tian‑lin, QI Xiu‑juan, ZHANG Qing‑hua, et al. Exploiting hydrophobic borohydride‑rich ionic liquids as faster‑igniting rocket fuels[J]. Chemical Communications, 2016, 52(10): 2031-2034.

    • 11

      WANG Yi, HUANG Shi, ZHANG Qing‑hua, et al. Nitrato‑functionalized task‑specific ionic liquids as attractive hypergolic rocket fuels[J]. Chemistry‑A European Journal, 2017, 23(51): 12502-12509.

    • 12

      JIN Yun‑he, WANG Bin‑shen, ZHANG Qing‑hua, et al. Synthesis and properties of triaminocyclopropenium cation based ionic liquids as hypergolic fluids[J]. Chemistry‑A European Journal, 2018, 24(18): 4620-4627.

    • 13

      ZHENG Bing‑xiao, ZHANG Yan‑qiang, ZHANG Suo‑jiang, et al. Azetidinium‑based hypergolic ionic liquids with high strain energy[J]. Chemistry Select, 2018, 3(1): 284-288.

    • 14

      WANG Kai, ZHANG Yan‑qiang, Shreeve J M, et al. Boronium‑cation‑based ionic liquids as hypergolic fluids[J]. Chemistry‑A European Journal, 2012, 18(38): 16931-16937.

    • 15

      LI Xing‑ye, WANG Chen‑bin, CHEN Fu‑xue, et al. Bishydrobis(tetrazol‑1‑yl)borate (BTB) based energetic ionic liquids with high density and energy capacity as hypergolic fuels[J]. Journal of Materials Chemistry A, 2017, 5(30): 15525-15528.

    • 16

      LI Xing‑ye, HUO Hong‑yu, CHEN Fu‑xue, et al. Cyanotetrazolylborohydride (CTB) anion‑based ionic liquids with low viscosity and high energy capacity as ultrafast‑igniting hypergolic fuels[J]. Chemical Communications, 2017, 53(59): 8300-8303.

    • 17

      翁欣妍,杜宗罡,于君,等.含BH3(CN)BH2(CN)-阴离子的离子液体自着火过程的实验研究[J].含能材料, 2018, 26(7): 557-564.

      WENG Xin‑yan,DU Zong‑gang,YU Jun,et al. Experimental study of hypergolic process of ionic liquid with BH3(CN)BH2(CN)- anion[J]. Chinese Journal of Energetic Materials (Hanneng Cailiao), 2018, 26(7): 557-564.

    • 18

      Ramachandran P V, Kulkarni A S, Pourpoint T L, et al.Amine‑boranes: green hypergolic fuels with consistently low ignition delays[J]. Chemistry‑A European Journal, 2014, 20(51): 16869-16872.

    • 19

      GAO Hai‑xiang, Shreeve J M. Ionic liquid solubilized boranes as hypergolic fluids[J]. Journal of Materials Chemistry, 2012, 22(22): 11022-11024.

    • 20

      HUANG Shi, QI Xiu‑juan, ZHANG Qing‑hua, et al. Towards safer rocket fuels: hypergolic imidazolylidene‑borane compounds as replacements for hydrazine derivatives[J]. Chemistry‑A European Journal, 2016, 22(29): 10187-10193.

    • 21

      LI Xing‑ye, NAN Jia‑yu, CHEN Fu‑xue, et al. Exploring BH2CN‑based hydrophobic hypergolic fuels and effective fuel “additives”: imidazolylidene cyanoboranes[J]. Chinese Chemical Letters, 2018, doi.org/10.1016/j.cclet.2017.09.036, online.

    • 22

      WANG Xiao‑jun, ZHANG Li, Peter W, et al. General solution to the synthesis of N‑2‑substituted 1,2,3‑triazoles[J]. Organic Letters, 2010, 12(20): 4632-4635.

    • 23

      Greg K, Greg D, Tommy H, et al. Synthesis, characterization, and structural investigations of 1‑amino‑3‑substituted‑1,2,3‑triazolium salts, and a new route to 1‑substituted‑1,2,3‑triazoles[J]. Journal of Heterocyclic Chemistry, 2005, 42(1): 19-27.

    • 24

      Durgapal U C, Venugopal V K. Hypergolic ignition of rocket propellants with nitric acid containing dissolved nitrogen tetroxide[J]. AIAA Journal, 1974, 12(11):1611-1612.

    • 25

      Frisch M J, Trucks G W, Fox D J, et al. Gaussian09[CP], RevisionA.02, Gaussian, Inc, Wallingford CT, 2009.

    • 26

      史新辉.700种主要有机化合物的热容和生成焓[J]. 化学工程, 1989, 17(5): 39-63.

      SHI Xin‑hui. Heat capacities for 700 compounds[J]. Chemical Engineering, 1989, 17(5): 39-63.

王晨斌

机 构:北京理工大学化学与化工学院, 北京 100081

Affiliation:Beijing Institute of Technology School of Chemistry and Chemical Engineering, Beijing 100081, China

邮 箱:2120161245@bit.edu.cn

作者简介:王晨斌(1994-),男,硕士,主要从事含能材料研究。e‑mail:2120161245@bit.edu.cn

李兴业

机 构:北京理工大学化学与化工学院, 北京 100081

Affiliation:Beijing Institute of Technology School of Chemistry and Chemical Engineering, Beijing 100081, China

陈甫雪

机 构:北京理工大学化学与化工学院, 北京 100081

Affiliation:Beijing Institute of Technology School of Chemistry and Chemical Engineering, Beijing 100081, China

角 色:通讯作者

Role: Corresponding author

邮 箱:fuxue.chen@bit.edu.cn

作者简介:陈甫雪(1970-),男,教授,主要从事含能材料合成、手性合成研究。e‑mail:fuxue.chen@bit.edu.cn

compoundTgTm)/ ℃Td / ℃ρ / g∙cm-3η / mPa∙sΔHf / kJ∙g-1Ιsp / sρIsp / s∙g∙cm-3ID / ms
1/ 502251.086-2.3221.735913
2-42 / 222001.05170.01.8209.635390
3/ <-702331.02416.01.5201.735712
4/ <-702561.00232.51.2195.435523
5/ <-70157 / 2041.06010.12.4214.935533
UDMH[24]-57-0.790.490.81313.5-4.8
html/hncl/CJEM2018164/media/aa203810-5e89-4dbc-8081-01957bc4216e-image003.png

表1 三唑硼烷复合物的物化性质

Table 1 Physicochemical properties of N‑alkytriazole cyanoborane adducts

图1 化合物3与WFNA的滴落实验高速摄影照片

Fig.1 High‑speed camera photos that show a spatially resolved ignition event for a droplet of 3 falling into WFNA

image /

Tg is glass‑transition temperature. Tm is melt point (DSC, 5 ℃∙min-1). Td is decomposition temperature (onset, DSC, 5 ℃∙min-1). ρ is experimental density at 25 ℃. η is Viscosity at 25 ℃. ΔHf is heat of formation (Gaussian 09, MP2(full)/6‑311++G(d,p)). Ιsp is specific impulse (Explo5 v6.02, oxidizer N2O4 (equivalence ratio=1.0), isobaric conditions, equilibrium expansion, 7.0 MPa chamber pressure). ρIsp is density specific impulse. ID is ignition delay time.

无注解

  • 参考文献

    • 1

      李亚裕.液体推进剂[M]. 北京:中国宇航出版社, 2011: 1.

      LI Ya‑yu.Liquid propellant[M]. Beijing: China Astronautic Publishing House, 2011: 1.

    • 2

      田均均,张庆华.含能离子液体‑新型离子炸药和绿色推进剂燃料[J]. 含能材料, 2014, 22(5): 580-581.

      TIAN Jun‑jun, ZHANG Qing‑hua. Energetic ionic liquid‑new explosives and green propellant fuels[J]. Chinese Journal of Energetic Materials(Hanneng Cailiao), 2014, 22(5): 580-581.

    • 3

      Schneider S, Hawkins T, Rosander M, et al. Ionic liquids as hypergolic fuels[J]. Energy & Fuels, 2008, 22(4): 2871-2872.

    • 4

      HE Ling, TAO Guo‑hong, Shreeve J M, et al. Nitrocyanamide‑based ionic liquids and their potential applications as hypergolic fuels[J]. Chemistry‑A European Journal, 2010, 16(19): 5736-5743.

    • 5

      Joo Y H, GAO Hai‑xiang, Shreeve J M, et al. Inorganic or organic azide‑containing hypergolic ionic liquids[J]. Inorganic Chemistry, 2010, 49(5): 3282-3288.

    • 6

      Maciejewski J P, GAO Hai‑xiang, Shreeve J M. Synthetic methods for preparing ionic liquids containing hypophosphite and carbon‑extended dicyanamide anions[J]. Chemistry‑A European Journal, 2013, 19(9): 2947-2950.

    • 7

      ZHANG Yan‑qiang, GAO Hai‑xiang, Shreeve J M, et al. Ionic liquids as hypergolic fuels[J]. Angewandte Chemie International Edition, 2011, 50(41): 9554-9562.

    • 8

      LI Song‑qing, GAO Hai‑xiang, Shreeve J M. Borohydride ionic liquids and borane/ionic‑liquid solutions as hypergolic fuels with superior low ignition‑delay times[J]. Angewandte Chemie International Edition, 2014, 53(11): 2969-2972.

    • 9

      ZHANG Qing‑hua, YIN Ping, Shreeve J M, et al. Cyanoborohydride‑based ionic liquids as green aerospace bipropellant fuels[J]. Chemistry‑A European Journal, 2014, 20(23): 6909-6914.

    • 10

      LIU Tian‑lin, QI Xiu‑juan, ZHANG Qing‑hua, et al. Exploiting hydrophobic borohydride‑rich ionic liquids as faster‑igniting rocket fuels[J]. Chemical Communications, 2016, 52(10): 2031-2034.

    • 11

      WANG Yi, HUANG Shi, ZHANG Qing‑hua, et al. Nitrato‑functionalized task‑specific ionic liquids as attractive hypergolic rocket fuels[J]. Chemistry‑A European Journal, 2017, 23(51): 12502-12509.

    • 12

      JIN Yun‑he, WANG Bin‑shen, ZHANG Qing‑hua, et al. Synthesis and properties of triaminocyclopropenium cation based ionic liquids as hypergolic fluids[J]. Chemistry‑A European Journal, 2018, 24(18): 4620-4627.

    • 13

      ZHENG Bing‑xiao, ZHANG Yan‑qiang, ZHANG Suo‑jiang, et al. Azetidinium‑based hypergolic ionic liquids with high strain energy[J]. Chemistry Select, 2018, 3(1): 284-288.

    • 14

      WANG Kai, ZHANG Yan‑qiang, Shreeve J M, et al. Boronium‑cation‑based ionic liquids as hypergolic fluids[J]. Chemistry‑A European Journal, 2012, 18(38): 16931-16937.

    • 15

      LI Xing‑ye, WANG Chen‑bin, CHEN Fu‑xue, et al. Bishydrobis(tetrazol‑1‑yl)borate (BTB) based energetic ionic liquids with high density and energy capacity as hypergolic fuels[J]. Journal of Materials Chemistry A, 2017, 5(30): 15525-15528.

    • 16

      LI Xing‑ye, HUO Hong‑yu, CHEN Fu‑xue, et al. Cyanotetrazolylborohydride (CTB) anion‑based ionic liquids with low viscosity and high energy capacity as ultrafast‑igniting hypergolic fuels[J]. Chemical Communications, 2017, 53(59): 8300-8303.

    • 17

      翁欣妍,杜宗罡,于君,等.含BH3(CN)BH2(CN)-阴离子的离子液体自着火过程的实验研究[J].含能材料, 2018, 26(7): 557-564.

      WENG Xin‑yan,DU Zong‑gang,YU Jun,et al. Experimental study of hypergolic process of ionic liquid with BH3(CN)BH2(CN)- anion[J]. Chinese Journal of Energetic Materials (Hanneng Cailiao), 2018, 26(7): 557-564.

    • 18

      Ramachandran P V, Kulkarni A S, Pourpoint T L, et al.Amine‑boranes: green hypergolic fuels with consistently low ignition delays[J]. Chemistry‑A European Journal, 2014, 20(51): 16869-16872.

    • 19

      GAO Hai‑xiang, Shreeve J M. Ionic liquid solubilized boranes as hypergolic fluids[J]. Journal of Materials Chemistry, 2012, 22(22): 11022-11024.

    • 20

      HUANG Shi, QI Xiu‑juan, ZHANG Qing‑hua, et al. Towards safer rocket fuels: hypergolic imidazolylidene‑borane compounds as replacements for hydrazine derivatives[J]. Chemistry‑A European Journal, 2016, 22(29): 10187-10193.

    • 21

      LI Xing‑ye, NAN Jia‑yu, CHEN Fu‑xue, et al. Exploring BH2CN‑based hydrophobic hypergolic fuels and effective fuel “additives”: imidazolylidene cyanoboranes[J]. Chinese Chemical Letters, 2018, doi.org/10.1016/j.cclet.2017.09.036, online.

    • 22

      WANG Xiao‑jun, ZHANG Li, Peter W, et al. General solution to the synthesis of N‑2‑substituted 1,2,3‑triazoles[J]. Organic Letters, 2010, 12(20): 4632-4635.

    • 23

      Greg K, Greg D, Tommy H, et al. Synthesis, characterization, and structural investigations of 1‑amino‑3‑substituted‑1,2,3‑triazolium salts, and a new route to 1‑substituted‑1,2,3‑triazoles[J]. Journal of Heterocyclic Chemistry, 2005, 42(1): 19-27.

    • 24

      Durgapal U C, Venugopal V K. Hypergolic ignition of rocket propellants with nitric acid containing dissolved nitrogen tetroxide[J]. AIAA Journal, 1974, 12(11):1611-1612.

    • 25

      Frisch M J, Trucks G W, Fox D J, et al. Gaussian09[CP], RevisionA.02, Gaussian, Inc, Wallingford CT, 2009.

    • 26

      史新辉.700种主要有机化合物的热容和生成焓[J]. 化学工程, 1989, 17(5): 39-63.

      SHI Xin‑hui. Heat capacities for 700 compounds[J]. Chemical Engineering, 1989, 17(5): 39-63.