Migrating simulation of novel high-energy SMX-based propellants based on molecular dynamics

Abstract

Three 2,3-bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol tetranitrate (SMX)–based propellants were firstly reported, then the specific impulses of SMX-based propellants were calculated by the Energy Calculation Star program. Meanwhile, the migration property of the plasticizers and SMX was investigated by molecular dynamic method, and the main results as follows: the theoretical specific impulses of three SMX-based propellants all overpass 280 s, which suggests that they have the potential to be high-energy propellants. The migrating property of plasticizers in SMX-based propellants and ethylene propylene diene monomer (EPDM) insulation all decrease in the order Bu-NENA> BTTN> TMETN. Meanwhile, the plasticizers much easier migrate in EPDM insulation than in SMX-based propellants, and TMETN is significantly more difficult to migrate than the other. The glass transition temperatures (Tg) of GAP/Bu-NENA/Al/SMX, GAP/BTTN/Al/SMX, and GAP/TMETN/Al/SMX systems are 282.3 K, 278.1 K, and 287.6 K, respectively. Due to lower Tg of EPDM, the EPDM/plasticizer systems have no obvious glass transition between 233 and 323 K. The SMX is almost more difficult to migrate than plasticizers in SMX-based propellants while temperature is above 273 K, whereas it is contrary under 273 K.