US EPA

7694702 

Journal Article 

Effect of Coated Ammonium Dinitramide on the Properties of Nitrate-ester Plasticized Polyether Solid Rocket Propellants 

Pang, W; Li, J; Deluca, LT; Ke, W; Fu, XL; Zhong, F; Li, H; Ji, Y 

2018 

Yes 

Central European Journal of Energetic Materials
ISSN: 1733-7178 

15 

4 

590-609 

English 

10.22211/cejem/94785 

WOS:000457315700004 

Several industrial and research types of nitrate-ester plasticized polyether (NEPE) solid propellants were experimentally analyzed. In general, their compositions differed in the mass fraction of ammonium dinitramide (ADN), which was used as a promising highly energetic filler, as an alternative to ammonium perchlorate (AP). ADN exhibits high performance, low signature and non-polluting characteristics. The propellant composition without ADN, but with AP, was used as the reference. The microstructure and granularity distribution of the uncoated and coated ADN particles were experimentally analyzed. It was found that uncoated ADN particles exhibited irregular shape, while the ADN particles after coating are spherical. Because of their irregular shape, uncoated ADN particles caused inferior processability of the propellant slurry when added to the propellant formulation. Consequently, the NEPE propellants with coated ADN were studied in further detail. The rheological properties, energetic properties, mechanical sensitivities and combustion properties (burning rate and pressure exponent) of the NEPE propellants with coated ADN were studied and compared with the reference NEPE propellant. The addition of ADN particles to the propellant formulations increased the standard theoretical specific impulse and heat of explosion of the propellants, while decreasing the density. The propellants containing ADN particles were much more sensitive to impact and friction compared to the reference sample. Moreover, increasing the ADN mass fraction in the propellant formulation can significantly affect the combustion behaviour and increase the burning rate and pressure exponent compared to of the reference formulation. However it appears that ADN is a very promising candidate as a new energetic material in compositions of NEPE propellants, although several important questions concerning ADN's suitability, especially in the context of its sensitivity to friction and impact, remain to be answered. © 2018 Institute of Industrial Organic Chemistry, Poland. 

energetic materials; NEPE composite solid propellants; ADN; hazardous properties; combustion characteristics