Molecular Level Understanding of Compatibility of Energetic Binder PGN with Energetic Plasticizers

摘要

The essential idea of developing energetic binders and plasticizers is to enhance the thermal stability and energy content, improve the oxygen balance and burning behaviour of a formulation, reduce the glass transition temperature and improve other mechanical properties of the propellant.Present work deals with the effect of addition of five different energetic plasticizers i.e.bis (2, 2-dinitro propyl) acetal (BDNPA),dinitro-diaza-alkanes (DNDA-57), 1,2,4-butanetriol trinitrate (BTTN), N-N-butyl-N'(2-nitroxy-ethyl) nitramine (Bu-NENA) and diethyleneglyeol dinitrate (DEGDN) on the rheological and thermal properties of energetic binder poly glyeidyl nitrate (PGN).Rheological evaluation revealed that the viscosity of the binder is sufficiently lowered with the increase in flow behaviour on addition of 20％ (w/w) plasticizer.Addition of 20％ DEGDN has maximum effect on the lowering of viscosity of PGN.The results obtained for the mixtures of plasticizer and binder in the parameters of decomposition temperature (Tmax) and the format of the peak are comparable to the results obtained for the pure binder indicating the compatibility of these plasticizers with PGN.Quantum chemically derived molecular electrostatic potential (MESP) showed the possible sites of plasticizers and binder with the estimated deepest Vmin values and their magnitudes provide an insight for their mutual interactions.The relative trend of deepest Vmin values of plasticizer towards binder PGN is well correlated with the corresponding trend of ability of plasticizers towards reducing the viscosity of PGN.The information gathered in the present work would in general be valuable to design new plasticizers