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The spatial problem of internal explosive loading of an elastoplastic cylindrical container filled with water in Eulerian - Lagrangian variables using multigrid algorithms is considered. A defining system of three-dimensional equations of the dynamics of gas, fluid, and elastoplastic medium is presented. For numerical modeling, a modification of S.K. Godunov scheme of the increased accuracy for both detonation products and liquids, and elastoplastic container is used. At the moving contact boundaries “detonation products - liquid”, “liquid - deformable body”, the exact solution of the Riemann's problem is used. A time dependent model is used to describe the propagation of steady-state detonation wave through an explosive from an initiation region. In both cases, the initiation of detonation occurs at the center of the charge. Two problems have been solved: the first task for the aisymmetric position of the charge, the second for the charge shifted relative to the axis of symmetry. In the first task, the processes are two-dimensional axisymmetric in nature, in the second task, the processes are essentially three-dimensional. A comparison is made of the results of calculations of the first problem using a three-dimensional method with a solution using a previously developed two-dimensional axisymmetric method and experimental data. Good agreement is observed between the numerical results for the maximum velocities and circumferential strains obtained by various methods and experimental data. There is good agreement between the numerical results obtained by various methods and the known experimental data. Comparison of the results of solving the first and second problems shows a significant effect of the position of the charge on the wave processes in the liquid, the processes of loading the container and its elastoplastic deformation. The dynamic behavior of a gas bubble with detonation products is analyzed. A significant deviation of the bubble shape from the spherical one, caused by the action of shock waves reflected from the structure, is shown. Comparison of the results of solving the first and second problems showed a significant effect of the charge position on wave processes in a liquid, the processes of loading a container and its elastoplastic deformation. In particular, in the second problem, shock waves of higher amplitude are observed in the liquid when reflected from the walls of the container.

A one-step method of in situ polymerization of nylon 66/reduced graphene oxide (PA66/rGO) nanocomposites is first proposed, simply by introducing graphene oxide (GO) into PA66 salt with the existence of ammonium hydroxide. The GO is prereduced by the ammonium hydroxide at an early stage of the polymerization process and then grafted on the PA66 chains, accompanied with the thermal reduction of GO. The PA66 chains were grafted onto the GO nanosheets through the condensation between the oxygen-containing functional groups of the GO and the terminal amino ends of the PA66 chains. The effect of GO on the mechanical properties, especially tensile strength, of nanocomposites was investigated. The results revealed that the incorporation of a very small amount (about 1 wt%) of GO caused a significant improvement in ultimate tensile strength (about 17%). The SEM of the fracture surface of composites indicated a good dispersion of rGO in the matrix. Raman spectroscopy, thermogravimetric analysis (TGA), scanning electron microscope (SEM), Fourier transformed infrared spectroscopy (FTIR), and XRD patterns of rGO, which was isolated from nanocomposites, revealed that the GO nanolayers were simultaneously reduced and PA66 chains were grafted on the rGO nanosheet during the polymerization process. The rGO grafted with the PA66 chain increases its compatibility in the PA66 matrix and effectively enhanced the interfacial energy of the composites.

The thermal decomposition behavior of HBT was studied by TG-DSC thermal analysis method. The decomposition products of HBT were analyzed. TGA curves and differential thermal curves of HBT were measured in different heating rates. The activation energy and pre-exponential factor of HBT was separately calculated by Ozawa equation and Kissinger equation. Thermal decomposition Mechanism of HBT were derived by Ozawa equation and its possible mechanism function was got. The differential thermal curves of HBT prepared by different dispersants were measured and the kinetic parameters were obtained. These kinetic parameters are in good agreement. The test values of the HBT dispersed with acetone have a higher accuracy, so the activation energy calculated is more meaningful.

High-molecular weight nylon 66/modified clay (Mclay) nanocomposites with a low apparent viscosity were prepared by in-situ polymerization and post solid-state polycondensation. Thermogravimetric analysis and X-ray diffraction patterns of the Mclay revealed that cetyltrimethyl ammonium bromide successfully inserted into the interlayers of the clay. Scanning electron microscope images of the cross sections showed that the Mclay was well-dispersed in the nylon 66 matrix. The effects of clay on the mechanical, rheological, and thermal properties of the nanocomposites were investigated using an Instron 5969 machine, a capillary rheometer, and a differential scanning calorimeter. The results indicated that the incorporation of a very small amount of Mclay considerably decreased the shear viscosity of the nanocomposites and increased the melt index, acting as a viscosity reducer. More importantly, the mechanical properties and spinnability of the nylon 66/Mclay nanocomposites were not affected by the viscosity reducer.