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Ammonium nitrate (AN) as an ingredient for solid propellants has problems caused by a large volume phase change in normal operational temperature range, difficulty in keeping dry at relative humidities above 30%, 91 degrees F phase change making smaller AN particles causing propellant grain growth during temperature cycling, and caking behavior that creates a need for processing into propellant relatively soon after grinding to retain small particle sizes. Interference of propellant cure using isocyanate curatives commonly occurs due to moisture content in the AN. AN phase stabilization is typically accomplished by introducing another substance into the ammonium nitrate crystal structure. Salts containing ions larger or smaller than either ammonium or nitrate ions have been used. Since the U.S. military has decided not to use nickel or copper phase stabilizing agents, our laboratory has been looking for new materials for phase stabilizing ammonium nitrate for use in solid propellants. Use of N,N,N',N'-tetramethyl hexane-1,6-diamine appears to solve many AN problems. That is, elimination of phase changes, elimination of propellant grain growth during temperature cycling, lack of moisture for cure interference, and lack of caking in 50% relative humidity environments. How AN can be transformed into a well behaved oxidizer ingredient will be discussed., Presented at the JANNAF Propulsion (56th), Structures & Mechanical Behavior (39th), Propellant & Explosives Development & Characterization (35th), Rocket Nozzle Technology (26th), Safety & Environmental Protection (24th), Nondestructive Evaluation Joint Subcommittee (17th) Meeting, held in Las Vegas, NV on 14-17 Apr 2009.

A gas chromatograph technique for the analysis of NF3 is described wherein N2, CO(O2), NO, CF4, NF3, CO2, N2O, SF6 and possibly N2F2 are separated isothermally on a single column. In addition, a simple total reactive fluoride measurement is presented.

A gas chromatography technique for the analysis of NF3 is described wherein N2(O2), CO, NO, CF4, NF3, CO2, N2O, SF6 and possibly N2F2 are separated isothermally on a single column. In addition, a simple total reactive fluoride measurement is presented.

In an effort to help determine the feasibility of the Urea process for production of the amine fuels, AFRPL established an in-house program to develop a useful analytical technique for monitoring the critical DMU to UDMH reaction. It was the absence of such a technique that presented problems for Vicksburg Chemical Company during their production contract with AFLC. Using laboratory scale equipment, AFRPL produced UDMH using purified DMU. Analysis of both reaction mixture and distillate was accomplished during all of the synthesis runs. After a variety of attempts, it was concluded that analysis of the DMU to UDMH reaction is difficult and propably not useful. Thus, great care must be taken in the scale up of the Urea process.

A method and apparatus for continuous extraction of an ingredient from a sample employs a container having a solvent therein selected for is ability to extract the ingredient. The sample is held against a porous substrate having a lower portion which is located below the sample and placed in the solvent, and an upper portion which is located above the sample and exposed to a selected atmosphere. In a continuous supply from the container, solvent is caused to ascend the substrate by capillary action, penetrate the sample, extract the ingredient therefrom, and continue to ascend the upper portion of the substrate where it evaporates, depositing the extracted ingredient thereon. The upper portion of the substrate containing the ingredient may then be removed., Supersedes PAT-APPL-313 859-81, AD-D009 201.

Most hydroxyl equivalent weight analyses call for relatively large prepolymer samples which may be impractical when dealing with small research products. The following describes a semi-micro procedure using an acetic anhydride/N-methylimidazole (AA/NMIN) esterification. The semi-micro procedure when compared to the macro version had more scatter but accuracy was not significantly affected. The AA/NMIM method requires a polar solvent system which is necessary to form an ion intermediate, hence esterification of nonpolar prepolymers cannot be accomplished. Also presented is a semi-micro technique for determining the hydroxyl equivalent weight of nonhydrogen bonding prepolymers by measuring the free hydroxyl infrared absorbance. When the technique was compared to titrimetric methods, the differences were no greater than 6%. (Author)

Errors associated with current analytical methods for Inhibited Red-Fuming Nitric Acid (IRFNA) are discussed, and a unique spectrophotometer calibration technique for water is described. Comparative analyses of the above mixture for water using (1) the military specification and (2) the spectrophotometric methods clearly show the latter to be far more accurate and precise. (Author)