Polyethylene Glycol-Poly(2-Methyl-5-Vinyl Tetrazole) Polymer Blend (A desensitizing Binder for Propellants and Explosives)

Abstract : Miscible polymer pairs are formed with an energetic polymer, (poly(2- methyl-5-vinyl tetrazole), PMVT,, and a nonenergetic polymer, polyethylene glycol, PEG, of molecular weight 1000 to 4000. This polymer blend PEG-PMVT is formed from acetonitrile solution upon removal of the solvent. The blend also precipitates when a nonsolvent, hexane, is added to a solution of PEG-PMVT in acetronitrile at or below 0 C. With PEG E1000, blends have been formed with PEG:PMVT of 1:1 to 1:1.8 by weight. This blend has been characterized from its unique glass transition temperature, Tg, as well as formation of transparent films. Interaction between chains in the form of weak C-H..O hydrogen bonding has been identified from infrared spectroscopy. Polymer blends are not formed with PMVT and polypropylene glycol, PPG, with methyl side chains as well as polyols with hydroxy number 3 or more. A blend is formed, however in a narrow regime of temperature with PMVT and glycidylazide polymer, GAP. This polymer blend is found to be a desensitizing energetic binder for propellants and for plastic-bonded explosives in particular. A PBX composition containing 91 percent RDX by weight and 9 percent PEG-PMVT polymer blend has a drop-weight-impact sensitivity better than Comp B. Polyethylene glycol (PEG), Desensitizing binder, Poly(2-methyl-5-vinyl tetrazole) (PMVT), Miscible polymer pairs, Interpenetrating network, Energetic binder, Sympathetic detonation polymer blend.