Molecular Dynamics Simulation on Compatibility and the Glass Transition Temperature of HTPB/Plasticizer Blends

摘要

By means of full atomistic molecular dynamics (MD) simulation, the solubility parameters for hydroxyl-terminated polybutadiene (HTPB), dioctyl sebacate (DOS), dioctyl adipate (DOA), dibutyl phthalate (DBP), dioctyl phthalate (DOP), nitrated esters nitroglycerine (NG) and diethylene glycol dinitrate (DEGDN) are calculated and the results are in agreement with the literature values. Furthermore, in order to reveal the HTPB/plasticizer blend property, the specific volume vs. temperature curves of the blend systems are simulated by employing MD simulation to obtain the glass transition temperature (T_g). From the specific volume vs. temperature curve, the T_g of HTPB, HTPB/DOS, HTPB/DOA, HTPB/DBP, HTPB/DOP, HTPB/NG and HTPB/DEGDN are 197.54, 176.30, 183.11, 189.27,187.40, 200.03 and 205.31 K, respectively. It should be pointed out that as for HTPB and DOS, DOA, DBP, DOP, the solubility parameters are similar and there is only one glass transition of the blend system, these indicate that these studied blend systems are miscible, but HTPB/NG and HTPB/DEGDN are not miscible.