含能材料热动力学行为和热力学性质的研究进展

针对近年来含能材料热力学和热动力学分析研究方面所取得的一些进展进行了回顾和概述;对新型含能材料如含能离子盐、FOX-7及其衍生物、新型高能氧化剂及高能添加剂等的热动力学行为和热力学性质进行了系统总结.此外,介绍了目前最新的一些研究方法和理论,讨论了当前研究中存在的问题,同时对未来的发展方向进行了展望.     

三唑含能离子盐的热化学性质和热动力学行为

用微量热技术测量1,2,4-三唑硝酸盐(1a)、1,2,3-三唑硝酸盐(1b)、3,4,5-三氨基-1,2,4-三唑硝酸盐(2a)、3,4,5-三氨基-1,2,4-三唑二硝酰胺盐(2b)4种三唑类含能离子盐的溶解过程热效应、比热容(283KT353K)及非等温条件下的热分解过程.用处理实验数据和理论计算方法获得了1a、1b、2a、2b溶解过程的热化学方程式、微分溶解焓、摩尔溶解焓、动力学方程式、活化能、指前因子、283～353K温区内比热容随温度变化的线性关系式、标准摩尔热容CpΘ,m和285～353K温区以298.15K为基准的焓、熵和Gibbs自由能函数值.计算了热分解反应的动力学参数、热力学参数以及评估了1a、1b、2a、2b对热的抵抗能力.得到了化合物性质与分子结构之间内在关系的信息.     

国外含能材料的生物合成研究进展

生物合成是一个微生物催化反应过程,由有特定功能的微生物催化无毒的、可再生的原材料得到产物。近年来,生物合成在含能材料领域的应用受到了国外含能材料专家的广泛关注。本文将概述生物合成在含能材料中的应用研究进展,包括以木糖和葡萄糖为原材料,由生物合成法得到合成某些含能材料的重要前驱体丁三醇、三醋酸己内酯和间苯三酚等化合物;同时简要介绍了部分含能材料的可能生物合成路径,最后,对生物合成法在含能材料领域的应用前景进行了分析。     

共晶含能材料研究进展

共晶是不同种类的分子(两种或两种以上)通过氢键等分子间相互作用,形成具有特定结构和性能的多组分分子晶体,不同含能材料形成共晶可以有效改善炸药的感度、安全性等性能。针对目前高能炸药的改性需求,共晶在含能材料领域中的应用具有巨大的潜力。综述了共晶的形成原理及生长特性,总结了常见共晶的制备方法和表征方法,评述了含能材料共晶的研究现状和发展前景。     

高氮化合物及其含能材料

高氮含能化合物及其含能材料是新型含能材料领域的研究热点之一。相比于传统的含能材料,高氮含能材料具有很多优异或独特的理化性能和爆轰性能。本文综述了新型高氮化合物及其含能材料的研究进展,介绍了国内外近十年来众多研究小组的相关工作,重点阐述了四嗪、四唑和呋咱3大类高氮含能化合物的合成、性能及应用研究进展。结合作者的研究工作,进一步探讨了高氮含能化合物在钝感高能炸药、推进剂和新型气体发生剂等含能材料领域中的应用前景。     

含能盐和含能离子液体

近年来含能盐和含能离子液体由于其独特的性质而受到广泛关注。本文综述了多种含能盐和含能离子液体（阳离子包括三唑、四唑、双环唑、六次甲基四胺等;阴离子包括硝酸根、高氯酸根、硝基唑、叠氮根、四硝基铝、多腈基化合物、二硝基尿素等）的合成;结合其表征结果分析了阳离子上的取代基以及阴阳离子对它们的性能如熔点、生成焓、密度等的影响。对含能盐和含能离子液体在炸药和推进剂方面的应用进行了展望。     

吡唑含能离子盐的合成研究进展

吡唑环上有三个可修饰的碳位点和一个可修饰的NH位点,通过对这四个位点的修饰(主要是引入硝基、硝胺基、氨基、羟基以及形成稠环等),可设计出种类丰富的吡唑含能化合物.同时,相对于2,4,6-三硝基甲苯(TNT)、黑索金(RDX)、奥克托今(HMX)等常规含能化合物,吡唑含能化合物具有氮含量高、生成焓高及感度低等优势.近年来...     

裂解气相色谱法测定含能材料中氟橡胶

应用裂解气相色谱法测定了含能材料中氟橡胶的含量,方法中选用液体进样法,将试样（如聚黑-14及黑索今等样品,以及氟橡胶标准样品）溶解于乙酸乙酯中,分取其中1μL滴于热带探头的铂金带上,经红外灯烘干除去乙酸乙酯后引入于裂解器中,在600℃裂解8S,最适宜的进样量为108μg。在最佳测定条件下,测得的峰高值与氟橡胶的质量浓度在19．2～28．8g·L^-1范围内呈线性关系。对方法的精密度进行了试验,测得相对标准偏差（n=11）为0．13％。     

含能材料起爆过程“热点”理论研究进展

对含能材料起爆机理的深入了解是提高含能材料安全可靠性的根本。"热点"起爆机理是目前被广泛认可的一种理论。本文主要介绍了"热点"理论的产生历史和"热点"模型,以及从宏观和微观两个角度概括总结实验和理论上对"热点"形成机制的新研究成果。比较分析了"热点"模型的有效性,并提出了"热点"起爆理论中存在的一些问题和今后的研究方向。分析表明,"热点"起爆机理是一种重要的且比较复杂的理论,它不仅与含能材料分子结构特性有关,还与晶体缺陷类型以及外界能量注入方式有关。同时,它涉及到外界能量向材料内部热能的转化,并在热、力及化学反应耦合作用下发展的复杂的物理化学过程。因而,从原子分子层次分析微观结构与外界能量的耦合机制是深入理解"热点"理论的有效途径。     

氧杂环丁烷系列含能粘合剂的合成研究进展

新型含能粘合剂的出现进一步提高了固体推进剂的能量和性能。其中,在3-位取代含能基团实现氧杂环丁烷的含能化并以此类单体合成的含能粘合剂,由于其具有相对分子量和官能度可控性好、多分散性和玻璃化转变温度低而受到重视,引起广泛关注。     

Thermal Behaviour of Some Terpenoids

The terpenoids acetyl sitosterol, lupeol, acetyl diosgenin and stigmasterol were studied. Comparison of the thermogravimetric curves and the activation energies of the terpenoids suggested the following sequence of thermal stability: acetyl sitosterol < acetyl diosgenin < lupeol < stigmasterol. The DSC curves allowed determination of the melting points and the degrees of purity. Comparison of the TG and DSC curves revealed the presence of phase transitions without mass loss that were attributed to rearrangements in the terpenoid molecules. This revised version was published online in August 2006 with corrections to the Cover Date.     

低温热分析标准物质的研制

研制了两种0~100℃热分析标准物质,分别为金属镓和水杨酸苯酯标准物质。研制的标准物质具有良好的均匀性和稳定性,采用与NIST,LGC相应标准物质比较的方法定值。NIST为SRM 2234镓,其定值采用288.6~314.35 K范围内的绝热热量计测得温度及热量值;LGC用绝热法为水杨酸苯酯的熔化温度和熔化热定值,两种方法都可以直接溯源至SI单位。对定值结果的不确定度进行了分析和评定。镓和水杨酸苯酯标准物质的熔化温度分别为(29.77±0.20)℃(k=2),(41.81±0.34)℃(k=2);熔化热分别为(80.52±0.48)J/g(k=2),(88.94±0.62)J/g(k=2)。研制的两种标准物质满足国家标准物质的技术要求,申报已获批准。     

抗癌药倍半氧化羧乙基锗的热行为

本文用DSC,TGA,FTIR研究了抗癌药倍半氧化羧乙基锗(Ge-132)的热行为。结果表明试样在320℃以下时出现晶态一无定形态转变峰和分解峰,试样开始分解的温度是214℃,因而证明Minoru Tstsai对Ge-132热性质所作的结论:“Ge-132在低于320℃没有熔化和分解的迹象”不符合实际,     

用非等温DSC基于Harcourt-Esson方程估算含能材料热爆炸临界温度的一种简单方法

用合理假设,由Semenov热爆炸理论和基于Harcourt-Esson速率表达式非等温动力学方程 ,推导了估算含能材料热爆炸临界温度的一种简单方法。该计算式为 ,比较简单。从非等温DSC曲线上onset温度（ ）通过表达式 可得到 ,由方程 可求得 值,随后算出 。该方法计算结果与Zhang-Hu-Xie-Li方法结果相一致。     

Thermal Studies on Energetic Compounds

The nitrate complexes of copper, nickel and zinc with diethylenetriamine (dien) i.e. [Cu(dien)₂](NO₃)₂, [Ni(dien)₂](NO₃)₂·2H₂O and [Zn(dien)₂](NO₃)₂ have been prepared and characterised. Thermal studies were undertaken using TG-DTG, DSC, ignition delay (t _id) and ignition temperature (IT) measurements. Impact sensitivity was measured using drop mass technique. The kinetic parameters for both non-isothermal and isothermal decomposition of the complexes were evaluated by employing Coats-Redfern (C-R) method and Avrami-Erofeev (A-E) equations (n=2 and 3), respectively. The kinetic analysis, using isothermal TG data, was also made on the basis of model free isoconversional method and plausible mechanistic pathways for their decomposition are proposed. Rapid process was assessed by ignition delay measurements. All these complexes were found to be insensitive towards impact of 2 kg mass hammer up to the height limit (110 cm) of the instrument used. The heat of reaction (?H) for each stage of decomposition was determined using DSC.     

Thermal Behaviour of Bisitaconimide and Bisnadimide Blends

This paper describes the thermal behaviour of blends of bisitaconimide (I) and bisnadimide (N) resins of similar structures. Bisitaconimides/bisnadimides based on 4,4'-diaminodiphenyl ether (E);2,2'-bis[4-(4-aminophenoxy)phenyl]propane (B); 1,3-bis(4-aminophenyl)benzene(R) and 1,4-bis(4-aminophenyl)benzene (H) were prepared and were designated as E-I/E-N; B-I/B-N; R-I/R-N and H-I/H-N respectively. Itaconimides had lower melting points and curing temperatures than that of corresponding nadimides. The blends of bisitaconimides and bisnadimides were prepared in the ratios of1:3, 1:1, 3:1 by solution mixing (chloroform/acetone). A decrease in the melting point and characteristic curing temperatures was observed in the blends. Thermal stability of cured resin blends was only marginally affected by the blend composition. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermal Analysis of the High-Energetic Material HNF

In a search for new storable high performance propellants for the European Space Agency (ESA), the solid oxidiser hydrazinium nitroformate (HNF) has been identified as a very promising ingredient for a new storable composite propellant. The purity and stability of HNF after production are very important indicators for the quality of HNF. In order to characterise HNF,many thermal analysis techniques as DSC and TG/DTA were performed to obtain more information about its stability and its (in)compatibility with other materials. Also some less familiar techniques such as the vacuum stability test and microcalorimetry have been performed. In relation to the safety, a relation between the friction and impact sensitivity and the physical-chemical properties is made. This revised version was published online in July 2006 with corrections to the Cover Date.     

Miscibility and Thermal Behaviour of Poly(styrene-co-itaconic acid)/Poly(butyl methacrylate-co-4-vinylpyridine) Mixtures. Accessibility and Self-Association Effects

Summary: The miscibility and thermal behaviour of binary mixtures of poly(styrene-co-itaconic acid) containing 11 or 27 mol % of itaconic acid (PSIA-11 or PSIA27) with poly(butyl methacrylate) (PBMA)or poly(butyl methacrylate-co-4-vinylpyridine) containing 10 or 26 mol% of 4-vinylpyridine (PBM4VP-10, PBM4V-P26) were investigated by differential scanning calorimetry, scanning electron microscopy, FTIR spectroscopy and thermogravimetry. The results showed that 11 mol % of itaconic acid and 10 mol % of 4-vinylpyridine respectively introduced within the polystyrene and poly(butyl methacrylate) matrices induced the miscibility of this pair of polymers due to specific interactions of hydrogen bonding type with partial pyridine protonation that occurred between the two copolymers as evidenced by FTIR from the appearance of two new bands at 1607 cm⁻¹ and 1640 cm⁻¹. Increasing itaconic acid content from 11 to 27 mol % led to a decrease of the intensity of the specific interactions within PSIA-27/PBM4VP blends and is attributed to both accessibility and self association effects as evidenced by DSC from the change of the shape of the Tg- composition curves and by FTIR spectroscopy. As shown from the thermogravimetric study, the presence of these specific interactions delayed the anhydride formation and improved the thermal stability of the blends.     

New Energetic Polynitrotetrazoles

This combined experimental, theoretical and comparative study details the syntheses and chemical characterisation of two new energetic polynitromethyl tetrazole derivatives, namely, 2‐(2‐nitro‐2‐azapropyl)‐5‐(trinitromethyl)‐2 H‐tetrazole and its fluorine‐containing analogue 2‐(2‐nitro‐2‐azapropyl)‐5‐(fluorodinitromethyl)‐2 H‐tetrazole. Their crystal structures and energetic behaviour are compared to those of their starting materials, the ammonium salts of the corresponding 5‐(polynitromethyl)‐2 H‐tetrazoles. Additionally, the crystal structures of two further related polynitrotetrazoles are presented.     

Compression Behavior and Vibrational Properties of New Energetic Material LLM-105 Analyzed Using the Dispersion-Corrected Density Functional Theory

The 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) is a newly energetic material with an excellent performance and low sensitivity and has attracted considerable attention. On the basis of the dispersion-corrected density functional theory (DFT-D), the high-pressure responses of vibrational properties, in conjunction with structural properties, are used to understand its intermolecular interactions and anisotropic properties under hydrostatic and uniaxial compressions. At ambient and pressure conditions, the DFT-D scheme could reasonably describe the structural parameters of LLM-105. The hydrogen bond network, resembling a parallelogram shape, links two adjacent molecules and contributes to the structure stability under hydrostatic compression. The anisotropy of LLM-105 is pronounced, especially for Raman spectra under uniaxial compression. Specifically, the red-shifts of modes are obtained for [100] and [010] compressions, which are caused by the pressure-induced enhance of the strength of the hydrogen bonds. Importantly, coupling modes and discontinuous Raman shifts are observed along [010] and [001] compressions, which are related to the intramolecular vibrational redistribution and possible structural transformations under uniaxial compressions. Overall, the detailed knowledge of the high-pressure responses of LLM-105 is established from the atomistic level. Uniaxial compression responses provide useful insights for realistic shock conditions.