Structures and Binding Energies of Nitrate Plasticizers DEGDN, TEGDN, and Nitroglycerine

The interactions between nitrate plasticizer ingredients nitroglycerine, diethylene glycol dinitrate (DEGDN), and triethylene glycol dinitrate (TEGDN) have been investigated theoretically and experimentally. Density functional theory (DFT) and second order perturbation theory (MP2) calculations show that intermolecular N-O electrostatic interactions and hydrogen bonding between alkyl hydrogens and oxygen atoms govern the dimer structures, which have predicted binding energies ranging from 20.6 to 39.3kJmol(-1). Vibrational frequencies observed in the nitrate band fingerprint region of the infrared spectra are in good agreement with the DFT scaled harmonic frequencies. The relative volatility observed in thermal gravimetric analysis (TGA) measurements of the pure ingredients and their 1:1 mixtures show reasonable correlation with the DFT dimer binding energies. The similarity in the dimer binding energies of all three plasticizers suggest that their mixtures should be uniformly miscible.