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The chemistry and properties of polymers containing the “fire smart” moiety 1,1-dichloro-2,2-diphenylethene (DDE) are described. These polymers are typically derived from the bisphenol of chloral (bisphenol-C/BPC) and are low cost, easily processed, and have good mechanical properties and toughness under normal conditions. Under fire conditions, the DDE group undergoes an intramolecular rearrangement with the elimination of hydrogen chloride (a noncombustible gas) and intermolecular crosslinking to form an aromatic char residue in high yield. The flammability and mechanical properties of DDE-containing polymers are described.

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Peroxide-based explosives have become of increased interest mainly because they are easily prepared and are not detected by traditional detection devices. The thermal behavior of triacetone triperoxide (TATP), a cyclic peroxide explosive was characterized by Differential Scanning Calorimetry (DSC) and Thermal Gravimetric Analysis (TGA). Dynamic and isothermal methods were used to characterize the sublimation process and to measure the vapor pressure at a temperature range under exothermic decomposition. The enthalpy of sublimation and kinetic parameters were estimated from direct mass loss rate measurements. Melting point, decomposition temperature and enthalpies of transitions were determined and compared to other known materials. The values were also compared to other recently reported values. The results of this study will help in the development of standoff detection technologies for improvised explosive devices using peroxide based materials.

We report the preparation of explosives nanoparticles of RDX and TNT in a variety of substrates that include glass, silicon and stainless steel. The explosive nanoparticles were prepared by means of pneumatically assisted nebulization (PAN) using an electrospray (ESI) needle, which allowed for the direct deposit of the energetic material onto the substrate. The deposited nanoparticles were characterized by optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX) and Raman Microscopy. SEM micrographs showed that the process produced particles with a mean size in the range of 80 -500 nm and a narrow size distribution. For TNT, the process produced smaller particles with a narrower size distribution. The EDX spectrum showed the presence of carbon, nitrogen and oxygen consistent with the elemental composition of the energetic materials. The chemical properties of the nanoparticles were also determined by vibrational spectroscopy.