Nanocomposites are prepared from Na-montmorillonite and polyethylene oxide) or poly-[oxymethylene oligo(oxyethylene) ] and characterized by X-ray diffraction, impedance spectroscopy, DTA, and TGA. Two ordered phases with intersheet spacings of 13.6 and 17.7 A, accommodating either single or double polymer layers within the montmorillonite galleries, are formed with polymer/Na-montmorillonite stoichiometries of 0.15 and 0.30 g/g, respectively. Materials prepared with intermediate stoichiometries yield diffraction profiles characteristic of solid solutions of these two phases. The details of composition and structure provide strong evidence that the polymer conformation is not helical as in crystalline PEO but more closely resembles an adsorbed layer. Sodium salts such as NaC104 can also be incorporated into the polyether/clay phases. The double-layer phase exhibits a maximum stable ionic conductivity between 10-5 and 10"6 S cm-1 at 520 K.

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The thermal behavior of aluminum nanoparticles reacting with propylene oxide was investigated in normal incident shock waves. Their reactive temperature, which is about 2705±150K, was experimentally determined by the emission strength of AlO. The reactive products were evaluated by x-ray diffraction, which shows that several different phases of Al2O3 are produced in different temperature regions. The scanning electron microscopy image of the reactive products shows that some holes, which were produced in the process of aluminum nanoparticles violently reacting with suboxides of aluminum, are found on the surface of the products. The data of transmission electron microscopy indicate that the grain diameters of the products were within the range of 20–90nm. The geometry of propylene oxide was calculated and optimized using the Rb31yp function and the 6–311+g(d,p) basis set. The calculated results show that the diameter of the molecule is about 0.435nm. The process of vaporizing and condensing of propylene oxide was investigated by electron microscopy, and the results show that the average drop diameter is 4.03μm at t=70s and then is 2.06μm at t=120s. It suggests that the average drop diameters tend to range from several nanometers to tens of nanometers, which is very close to the diameter of aluminum nanoparticles (average of 70nm). Thus, we may consider them to react with each other in the gas phase in normal incident shock waves in the experiment.

Based on spectral investigation, the role of nanoaluminium in the combustion phase of pseudo-nanoaluminized micro-cyclic-[CH2N(NO2)]3 (RDX) induced by shock wave is determined. Time-resolved monochromatic emission spectra of AlO (Δν = −1, 0, +1 of X 2Σ+–B 2Σ+) indicated bimodal combustion behaviour as nanoaluminium burns in post-detonation of a nanoaluminized RDX (cyclic-[CH2N(NO2)]3) explosive under an Ar atmosphere, which is in accord with the theoretical reaction temperature. As oxygen replaces Ar, a single emission peak of AlO is observed. The morphology of the condensed products is evaluated by transmission electron microscopy and scanning electron microscopy. Analyses of x-ray diffraction and XPS are also performed, concluding that only nano-α-Al2O3 is present in the O2 atmosphere experiments, whereas in the Ar atmosphere, metastable γ- and θ-Al2O3 also exist. AlN is one of the condensed products in Ar atmosphere experiments, which should form at the end of combustion as γ-and θ-Al2O3.

The effects of copper micro-particles on the detonation characteristics of RDX powder were investigated in a horizontal shock tube with internal dimensions of 100 mm diameter and 4 m length using an instantaneous spectrum detection apparatus. The emergence time and emission spectral intensity of the main products such as NO2, H, C2, O, CO, CH2O, CO2 and H2O were observed by a TDS5054 oscilloscope. With or without the addition of copper micro-particles into RDX, NO2 appears first in every experiment, which is in agreement with theoretical results. However, the addition of copper micro-particles to RDX can shorten the emergence time by 7–18%; it can also increase the peak blast pressure by about 133%. In addition, O2, H2O and CH2O in various quantities were introduced into this experiment, respectively, which indicate that O2 can obviously affect the results that may shorten the emergence time of NO2 by 31% and increase the peak blast pressure by 167%.