A New Method Rapidly Measuring Nitroglycerin in the coating of the rocket propellant

In this paper an application of thermogravimetric-derivative thermogravimetric analysis (TG-DTG) to the measurement of the nitroglycerin (NG) in thc coating of the rocket propellant was developed. In comparisons with gas chromatography (GC) and weight method (WM), TG-DTC has been confirmed to he even more available to measure rapidly migration of NG in thc coating. The new method is accurate to within ± 0.5% and its standard deviation is O.1. The method is of actual significance in respect of thc investigation of the migration regularity of plasticizer, the selection for coating materials and the prediction of service life of the solid propellants.     

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。     

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.     

The effect of vacuum and radiation on solid propellant properties

To understand the changes occurring in solid propellants on storage under space environments, the effect of vacuum and radiation on different propellants were studied. It was found that propellants lost weight on vacuum storage and that the rate and extent of weight loss depended upon the plasticizer content, the exposed surface area and the vacuum level. Mechanical properties and burning rates were practically unaffected and the effect on thermal decomposition was marginal. On the other hand, irradiation with gamma rays resulted in a drastic deterioration of mechanical properties and in a large increase in the rate of thermal decomposition at 225 °C. Radiation had no effect on burning rates.     

影响固碱锅使用寿命的主要因素

着重分析影响固碱锅使用寿命的因素:碱液的起始浓度、最高熔碱温度、火焰加热方式、升温速度等,提出了延长固碱锅使用寿命的措施。     

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.     

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。     

固相微萃取的心脏——涂层

固相微萃取是一种简单高效的新型预处理技术,涂层作为萃取头的核心部分,在萃取过程中发挥着重要作用。本文对涂层进行了概述,介绍其萃取机理、涂渍技术以及新型涂层研究发展与应用的情况。     

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。     

延长固碱锅使用寿命的探讨

介绍了天津渤天化工有限责任公司固碱锅的使用情况,分析了损坏原因,提出了延长固碱锅使用寿命的措施。     

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。     

Service life prediction of organic coatings: electrochemical impedance spectroscopy vs actual service life

Electrochemical impedance spectroscopy (EIS) is used to derive an expression for predicting the service life of organic coating in a C4-type environment (industrial and costal areas with moderate salinity) as defined in ISO 12944 standard for paints and varnishes—corrosion protection of steel structures by protective paint systems. Three coating systems with a record of 2, 5, and 10 years of durability were selected for the study. The selection was also based on proven composition and dry film thickness (DFT) of the coatings as per ISO 12944. Electrochemical impedance measurements of the paint-coated panels were carried out by exposing the coated mild steel panels without scribe in different corrosive environments such as immersion in NaCl solution, neutral salt spray, etc. Neutral salt spray exposure was found to be the most severe corrosive environment among all the three coating systems. In most of the cases, EIS gave early indication of coating failure when compared to visual defects such as blistering and over-film corrosion.     

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.     

超细高氯酸铵的制备及其在固体推进剂中的应用

总结了超细高氯酸铵的制备方法,主要包括超临界流体法、机械研磨法、气流粉碎法、喷雾干燥法、冷冻干燥法、反溶剂重结晶法等,并结合国内外主要生产厂家的实例,介绍了其在固体推进剂中的应用.     

F2型离子膜电解槽活性涂层的最佳经济寿命

以太原化工股份有限公司氯碱分公司离子膜分厂F2型离子膜电解槽实际运行参数为依据,对该种电解槽的阴、阳极活性涂层性能衰减情况进行经济分析,并计算出电解槽活性涂层的最佳经济寿命。     

Erosive burning of a solid propellant in a supersonic flow

We present results of an experimental study of burning of a ballistite solid propellant (gun powder H) in a supersonic flow. It is shown that the criterial dependence of the erosion coefficient on the Vilyunov parameter obtained on the basis of experimental results in a subsonic and a supersonic flow describes satisfactorily experimental data for a supersonic flow in the examined range of Mach numbers M=1–2.8 as well. A more correct approximation formula for the range of parameters considered is derived. The specific features of the flow along the surface of a solid propellant at M>1 is analyzed, and this analysis has revealed some problems in the interpretation of experimental data. Translated fromFizika goreniya i Vzryva, Vol. 34, No. 1, pp. 61–64, January–February, 1998.     

CL-20在推进剂和发射药中的应用

对CL-20在国内外推进剂和发射药中的研究应用进行了综述。含cL一20的推进剂虽然感度稍高,但有着输出能量高、低特征信号及燃烧产物对环境污染小等优点。CL-20作为低敏感、高能填充剂可用于制造高能、低敏感发射药,在某些推进剂和发射药配方中得到了应用。