Thermoplastic polyurethane elastomers (TPU) with tetrahydrofuran-ethylene oxide random copolyether and/or polyethylene oxide as soft segments and addition products of isophorone diisocyanate with 1,4-butanediol as hard segments were synthesized and characterized. The analyzed results indicated that the obtained TPU shows excellent mechanical properties (σm=9-11MPa, εm=500%). The glass transition temperature is as low as 213K. Especially, the product is plasticizable with nitroester and the plasticizing ratio of nitroester to the TPU is as high as 4.The maximum specific impulse of AP/A1/TPU is as high as 2598N·s/kg-2648 N·s/kg. The propellant samples were made with mixing-rolling-extrusion technique. The composition of propellants is W_(TPU) 10%-20%, W_(AP) 40%-60%, W_(Al) 10%-20%, W_(NG) 15%-25%. Propellant mechanical properties were measured asσm=0.66MPa (293K), εm=183% (293K) andEm =47% (233K). With no combustion catalysis, the pressure exponent is as low as 0.36. The application of synthesized TPU to modified double base propellant showed a promising future, with the addition of about 2% TPU to NG/NC/RDX system. The low temperature mechanical properties were remarkably improved and the content of RDX is able to increase from about 50% to 60%, meanwhile, the burning rate exponent is not changed. All the results indicated that this novel TPU posses a great potential application in solid propellants.
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