Synthesis, Characterization, and Rheological Evaluation of 1,3-Diazido-2-ethyl-2-nitropropane as an Energetic Plasticizer

Abstract

Abstract An energetic plasticizer, 1,3-diazido-2-ethyl-2-nitropropane (DAENP), was synthesized and characterized in good yield and high purity. DAENP is synthesized in three steps: 1) 1-nitropropane is condensed with formaldehyde to yield 2-ethyl-2-nitro-1,3-propane diol; 2) 2-ethyl-2-nitro-1,3-propane diol on tosylation gave 2-ethyl-2-nitro-1,3-bis(p-toluene sulfonyl) propyl ester; 3) azidation of the tosylated compound gives DAENP. The product was characterized by elemental analysis, Fourier transform infrared (FTIR) spectroscopy and 1H-NMR and purity was tested by high-performance liquid chromatography (HPLC). Thermal studies revealed that DAENP is thermally stable up to 196°C, has high energy output of the order 2,056 J/g, and a very low glass transition temperature (−96.76°C). DAENP is compatible with energetic binders like glycidyl azide polymer (GAP), 3,3-bis (azido methyl)oxetane–tetra hydroxyl furan (BAMO-THF) copolymer, and poly-3-nitrato methyl-3-methyl oxtetane (poly NIMMO or PLN). Rheological and thermal data showed that it can be used successfully with these binders. Keywords: azido plasticizerenergetic binderspropellantssynthesisviscosity Acknowledgement The authors are thankful to Dr. A. Subhananda Rao, distinguished scientist and director of the High Energy Materials Research Laboratory (HEMRL), Pune, India, and Dr. Amarjit Singh, associate director of HEMRL, for their encouragement.