Molecular dynamic simulations and experimental study on pBAMO-b-GAP copolymer/energetic plasticizer mixed systems

In order to investigate the effects of plasticizers on the binding energy, solubility parameter and mechanical properties of pBAMO-b-GAP copolymer (the copolymer of 3,3′-bis(azidomethy) oxetane and glycidyl azide polymer), the related copolymer/plasticizer mixed systems were established by molecular dynamics simulations. Besides, the mechanical properties of the formulas based on pBAMO-b-GAP containing the three energetic plasticizers were also studied experimentally. The results showed that all involved energetic plasticizers could be miscible with the pBAMO-b-GAP. The order of binding energy was theoretically found to be pBAMO-b-GAP / BuNENA > pBAMO-b-GAP/ TMETN > pBAMO-b-GAP/ DIANP which was consistent with the trends of the experimental tensile strength values of three mixed materials. Excitedly, the DIANP showed strongest effects among the three plasticizers on improving the toughness of the copolymer according to the calculation of Cauchy pressure and experimental value of elongation. For the pBAMO-b-GAP copolymer, the DIANP could be a promising plasticizer and compolymer/plasticizer mixed system was suitable used as binder in azido polyether-based propellants.