| As the development trend of molecular Chemistry penetrating to material Chemistry, the study of intermolecular interactions occurring in composite materials has become a hot scientific field and drawn much, more attention of chemists and materials scientists. Through theoretical study in this thesis, the intermolecular interactions of TATB (1,3,5-Triamino-2,4,6-Trinitrobenzene,) polymer-bonded explosive (PBX) was studied. And from the point of view of studying supermolecular configuration or on the molecule level, the interface action of materials was explained. The study on the intermolecular interactions would provide much data and theory guidance for the direction of producing PBX based on TATB.The supermolecular system of TATB/polymer was simulated and computed in virtue of quantum Chemistry and computational Chemistry. According to the computational condition and method, semiempirical Molecular Orbital methods (MO) and Molecular Mechanics (MM) were chosen. With regard to the first method, that was MO, AM1, PM3, MNDO and so on were involved in it. And MM mainly included PCFF or COMPASS force field. Then with the aid of MM and MO, the relative comparison between the computed binding energies of different method or force field could make certain that the results would be trusted. Besides these, constructing model was of importance and its process was summarized in detail. Because MO can only optimize gas-phase supermolecules, which decided that only few atoms had to be chosen, atomic cluster model was adopted in both MM and MO optimization. Above all, the "Principle of dimension matching" was summarized from the practice, so that the effect of chain-terminating atoms would be ignored and the deviation of simulation was reduced. The relation between the binding energies of TATB/polymer and the chain series n was explored . From this point of view, we proved that following the "Principle of dimension matching" was of necessity.By the aid of chemistry instinct, different interacting manners were searched in detail firstly. Then a series of possible configurations were optimized. And the optimized configurations must reflect the characteristics of sub-system. Though it was impossible to gain an absolute least energy, the relative least energies of series TATB/polymer could be gotten. Significantly, the relative meaningful results would satisfy the needs of comparison. Concerning the calculation of binding energies for these copolymerized compound concerned and TATB, the "Principle of monomer or component addition" should befollowed. Especially for these copolymerized compounds with similar configuration, the results were authentic.Through analysis of linear correlation between the binding energies which were computed by three MO methods and MM with different force fields, the conclusion was drawn that the correlation of energies computed by MO and COMPASS was superior to that of energies of MO and PCFF computation. When individual binding energies of supermolecule such as TATB/PVA and TATB/PVB were excluded reasonably, the correlative coefficient of MO method and the COMPASS force field was up to 0.96. After the binding energies were wholly compared according to the sequence of energy's numerical value, these energies of TATB and such polymers which included PVB (or PVA), PAN, PVDF, nylon, F2311 and F2603 were much greater, which established the base for the selection of bonds and design of PBX. |
