固体推进剂老化性能研究进展

研究固体推进剂的老化性能,预测其安全储存寿命,对弹药安全储存具有重要意义。本文从固体推进剂的老化性能机理、影响因素、测试方法以及储存寿命预测等方面综述了近年来国内固体推进剂老化性能的研究进展,认为固体推进剂的老化失效主要是由黏合剂氧化交联所致,推进剂自身的组成、结构和力学性能是决定其老化性能的内因,而外部因素主要有环境温度、湿度等。研究手段多采用分析仪器与实验相结合的方法,以缩短实验周期,提高结果准确性。以计算机为载体的多尺度模拟研究将是今后固体推进剂性能研究的重点。     

Molecular structure of the ideal solid propellant binder

A study has been conducted to investigate the relationship between binder molecular structure and the mechanical/rheological properties of solid propellants. Beginning with the mechanical property requirements dictated by the motor grain operating conditions as well as rheological constraints imposed by available processing technology, the approach taken was to work backwards to obtain the ideal molecular structure of a solid propellant binder. Structural/processing requirements were determined from the demands of three typical rocket motor applications: space transfer, launch vehicle/ballistic missile, and tactical air-to-air. Three general formulation approaches to meet the demands of these applications were considered. These include traditional composite and nitrate ester plasticized formulation approaches, in addition to a hypothetical all-binder propellant. For each of these three formulation approaches, a variety of polymer molecular characteristics were defined in terms of molecular weight, crosslink density, solubility parameter, chain stiffness, monomeric friction coefficient, volume fraction filler, and volume fraction plasticizer. Characterization data for ten polymeric binder systems are reported to show how their molecular architecture influences the resulting propellant properties.     

铝/冰固体推进剂的改良

针对如何提高铝/冰固体推进剂的综合性能,从氧化剂和燃料两方面进行了概述,指出引入H_2O_2和AlH_3均可提高推进剂的比冲,还可调节其燃烧性能;并对铝/冰固体推进剂的发展方向进行了展望。     

New technologies to determine solid fat content on-line

The determination of solid fat content (SFC) is an important analytical procedure in the food industry. The most common way to determine SFC is by low-resolution pulsed NMR (p-NMR). Although this technique is very sensitive and easy to use, it has the disadvantage that it cannot be used for on-line measurements. The present work compares new technologies to determine SFC on-line. On-line ultrasonic spectroscopy and NMR-MOUSE (NMR mobile universal surface explorer) techniques were compared with off-line p-NMR measurements and there was a good correlation between the values obtained. Ultrasonic measurements accurately described the SFC variation, whereas NMR-MOUSE determinations need to be improved to some extent owing to a strong temperature and motion dependence. These two techniques can be used as on-line methodologies to determine SFC during the crystallization of fats.     

固体推进剂用含能胶粘剂的研究进展

介绍了含能胶粘剂的改性机制,特别综述了叠氮[聚叠氮缩水甘油醚、3,3-双(叠氮甲基)氧丁环以及3-叠氮甲基-3-甲基氧丁环均聚物等]胶粘剂、硝酸酯类(聚缩水甘油硝酸酯、聚缩水甘油醚硝酸酯等)胶粘剂以及其他含能胶粘剂的优缺点和应用范围。最后展望了含能胶粘剂的未来发展方向。     

复合固体推进剂用增塑剂的研究进展

综述了非极性和极性复合固体推进剂用增塑剂的研究进展,包括其种类、研究现状和优缺点。对新型增塑材料——离子液体进行了展望。以期为复合固体推进剂用增塑剂的合成和应用研究提供参考。     

The migration of plasticizer in solid propellant grains

The migration of the plasticizer, dioctyl adipate (DOA) in the accelerated ageing of composite propellant has been studied. The method is based on the extraction of DOA with carbon tetrachloride and its estimation by gas chromatography. The concentration of DOA in the propellant at different distances from the insulation was determined after a definite ageing period and compared with the initial DOA concentration. The effect of (a) the ageing period, and (b) the ageing temperature on the degree of migration was examined. The present studies confirm the existence of plasticizer migration in the propellant adjacent to the insulation, during ageing.     

二聚酸二异氰酸酯在固体推进剂中的应用

简介了二聚酸二异氰酸酯(DDI)的主链结构及物性指标,详细叙述了DDI在丁羟(HTPB)推进剂药柱及绝热层、衬层、隔层中的应用情况,同时概括了其在聚醚推进剂和聚酯推进剂中的应用进展,认为绿色、无毒及来源于可再生原料的DDI是开发双推力推进剂、固体脉冲推进剂、富燃料推进剂及大型固体航天助推器推进剂的重要原材料,进行DDI的开发和应用对提高我国战术、战略武器的性能具有极大的促进作用。     

纳米材料在固体推进剂中的应用进展

从纳米含能材料、纳米金属粉、纳米催化剂及纳米碳材料4个方面综述了纳米材料在固体推进剂中的应用进展,归纳了各类纳米材料的特点及其在固体推进剂应用中存在的问题。指出了未来的研究方向,如纳米材料在固体推进剂中的分散技术、影响纳米材料微观形貌和粒度的因素、纳米材料在固体推进剂中的催化作用机理及利用纳米材料改善固体推进剂的力学性能等。     

无氯氧化剂在洁净固体推进剂中的应用

为满足目前固体火箭推进剂在应用过程中产生的环境相容性要求,对几种无氯氧化剂在洁净固体推进剂中的应用进行了综述。针对固体推进剂燃烧产物中HCl对环境产生的危害,分析了几类推进剂的抑氯机理,并着重从氧化剂的角度介绍多种无氯高能氧化剂在固体推进剂中的应用,分析了无氯氧化剂的特点及在推进剂应用过程中面临的问题,提出了洁净固体推进剂的重点研究方向,促进洁净固体推进剂的广泛应用,降低HCl对环境的危害。     

固体推进剂热安全性研究进展

综述了近年来固体推进剂热安全性的研究进展,认为固体推进剂发生热爆炸主要是由于推进剂生热速率大于散热速率导致热量累积。影响推进剂热安全性的因素主要由其组成、形状和尺寸等内因,以及贮存环境、老化时间等外部因素构成。固体推进剂热安全性研究多采用分析仪器与实验相结合的方法,借助计算机模拟仿真研究将是今后固体推进剂性能研究的重点。     

高能固体推进剂用粘合剂的研究进展

较为系统的从双基推进剂、复合固体推进剂、改性双基推进剂和NEPE推进剂等方面综述了其所用粘合剂的种类及其研究发展概况。介绍了当今新型含能粘合剂的类别和发展状况,并根据目前推进剂的发展要求,指出其粘合剂的发展趋势是含能化的热塑性弹性体。     

复合固体推进剂中固体填料的安息角测试与仿真

复合固体推进剂含有固体颗粒较多,离散单元法是一种适合固体推进剂生产过程数值仿真的有效方法,颗粒物料的接触参数是保证离散单元法仿真精度的关键。本文以复合固体推进剂的主要组分铝粉和高氯酸铵固体颗粒为研究对象,通过实验测试获得了相关物料的安息角,利用专业离散元软件EDEM仿真模拟了安息角测试实验过程,建立了物料安息角与接触参数之间的联系。研究表明,滚动摩擦系数和滑动摩擦系数越大,安息角越大,物料流动性越差。对比仿真与实验结果,通过逆向反推法确定了物料的滑动摩擦系数和滚动摩擦系数两个关键接触参数。铝粉与高氯酸铵1∶2混合颗粒的滑动摩擦系数为0.2,滚动摩擦系数为0.05。为固体推进剂加工生产过程离散元数值仿真提供了关键基础数据。     

Experimental studies of the ignition of a solid propellant in water

The ignition of a solid propellant in water by means of an unsealed system of ignition in the form of an open channel with a heating coil placed in the channel is considered. The ignition system operates according to the principle of creation of extreme conditions of water boiling in the channel with heat supply from an electrical heater. It was established visually that the heating of the walls is preceded by a preliminary period connected with the change in the state of aggregation of water. The system was tested on solid-propellant specimens. Translated fromFizika Goreniya i Vzryva, Vol. 35, No. 3, pp. 52–57, July–August 1999.     

延长固体推进剂适用期的研究进展

对改善推进剂工艺性能的文献进行了综述,包括对异氰酸酯改性、固化催化体系、工艺助剂和添加螯合剂的研究等,建议以三苯基铋延迟快速固化催化体系为基础,综合各种延长适用期、改善工艺性能的方法,解决二聚酸二异氰酸酯(DDI)在实际应用中的问题,推动DDI的实用化进程。     

复合固体推进剂药浆工艺性能概述

综述了国内外关于HTPB、NEPE两类复合固体推进剂药浆工艺性能研究进展,结合其各自应用背景及组成特点,分析了这两类推进剂药浆流变特性等工艺性能及其主要影响因素,并提出了未来复合固体推进剂工艺性能的重点研究方向。     

Mechanical aging behavior of styrene‐butadiene rubbers evaluated by abrasion test

The ring‐shaped styrene‐butadiene rubbers (SBRs) test pieces ran on a rotating stainless‐steel ring using an abrasion tester to evaluate the changes in the mechanical properties, such as the tensile storage modulus and tan δ values, the modulus at 300% elongation, and the strength and extension ratio at the breaking point, after a mechanical aging process. The surface of the SBR test pieces and the formed rubber debris after the running experiment was investigated using scanning electron microscopy. A change in the crosslinking density of the SBRs and the analysis of the isolated free polymers showed the occurrence of bond scission of the copolymer chains. On the other hand, the mechanical properties of whole SBR samples showed only a small change during the mechanical aging test. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

HTPB推进剂贮存老化建模及寿命预估研究综述

HTPB复合固体推进剂是火箭发动机的动力之源,其贮存寿命和性能优劣决定了火箭发动机的寿命和作战性能的发挥,因而研究HTPB复合固体推进剂的贮存老化模型及寿命预估具有重要的军事和经济意义。本文对复合固体推进剂贮存老化性能的研究方法进行了介绍,并综述了国内外贮存寿命老化建模的研究进展,针对推进剂实际贮存可能出现的问题对未来贮存寿命预估的发展趋势进行了预测。研究结果表明,现代仪器的运用可以弥补传统仪器在固体推进剂老化性能研究上的不足,但是还存在研究手段单一、测试方法存在误差、没有形成统一的系统等缺点;推进剂的老化过程比较复杂,结构完整性分析和老化试验相结合的方法可以对推进剂贮存性能和寿命预估进行系统性的研究,得到的结果更准确,可靠性更高。分段老化建模作为推进剂寿命预估研究的新方向,具有很大的发展空间。     

Dynamic rheological behavior of poly(ether ketone ketone) from solid state to melt state

High performance thermoplastic poly(ether ketone ketone) (PEKK) polymers with various meta phenyl links ratio were investigated by dynamical mechanical analysis. Analyses were carried out in a wide range of temperature from solid state (torsion rectangular mode) to the melt state (torsion parallel plates mode) as function of thermal history and environmental conditions. In the solid state, this study was focused on the secondary relaxations in the vitreous state. A complementary investigation conducted with different poly(aryl ether ketones) allowed us to propose a molecular interpretation of PEKK sub‐vitreous relaxations. In the molten state, storage modulus (G′), loss modulus (G″), storage viscosity (η′), and loss viscosity (η″) were studied to determine zero shear‐rate viscosity (η₀) and thermal activation energy E_a. Master curves were built and the shift factor a_T was determined. Thermal activation energies were extracted from an Arrhenius model on the shift factor temperature's dependency. Finally, E_a and η₀ were determined thanks to the dynamic viscosity fit with Cross model and Cole–Cole representation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46456.