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4,10-Dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane (TEX), a well-known nitramine category explosive, is much less sensitive to impact and friction stimuli as compared to the familiar explosives, RDX and HMX. TEX is currently produced on pilot plant scale and is being pursued as an insensitive explosive. Herein a newer, improved, efficient, and high yielding protocol is developed for the synthesis of TEX by using solid acidic silica sulfuric acid as an efficient and recyclable catalyst. Sequentially for process parameters optimization, a study was carried out with variation of catalyst loading, nitric acid, and mole ratio of reactants. The process scale-up is also achieved successfully.

The present study portrays the investigations on the optimization of the K2CO3-catalyzed synthesis of sucrose–coconut fatty acids esters. Determination of the hydroxyl value (HV) and the saponification value (SV), as well as Fourier transform infrared (FTIR) analysis, provided an understanding of the progress of transesterification, as a function of temperature (120–140 °C), holding period (30–150 min), catalyst concentration (1%–4%), molar ratio of sucrose to fatty acid methyl esters (FAME) (M = 0.364–6), and molecular weight of fatty acids. Bimolecular second-order kinetic model based on equal transesterification opportunity for all hydroxyl groups of sucrose/partial esters and that based on preferential transesterification of 6 −OH of the glucose unit in constant volume batch reactor were developed using integral and differential methods. The dependence of selective and nonselective kinetic models on the number and nature of hydroxyl groups in the sucrose were investigated. The changes in viscosity of ...

Polyamidoamine (PAMAM) dendrimer of zero generation was synthesized and characterized by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopic techniques. A novel chemistry has been developed to synthesize polyurea microcapsules containing solvent and linseed oil as the active healing agent by interfacial polymerization of commercial methylene diphenyl diisocyanate (MDI) and dendritic 0.0 G PAMAM capable of cross-linking to form a shell material. Spherical with some irregular shape microcapsules were observed with average diameter from 20 to 270 μm at different agitation rates (3000–8000 rpm). Interfacial interaction between polyurea microcapsules and polyurethane (PU) coating were studied by FTIR, and this showed that chemical bonds were formed by the reaction between isocyanates and the amine groups present on the wall of microcapsules. The thermal stability of the microcapsules showed that prepared microcapsules experienced excellent stability up to 380 °C. The anticorros...