Method for determining the order of reactivity of active hydrogen-containing components in propellants and curing agents

Abstract

The invention provides a determination method for the reaction activity order of active hydrogen-containing components and a curing agent in a propellant, wherein the method is applied to the field of nuclear magnetic analysis of spaceflight fuels. The method comprises the following steps: determination of a detection object; preparation of detection samples; selection of detection conditions; implementation of sample detection; and processing of detection data. According to the invention, a mixed uniform system of active hydrogen-containing components and toluene diisocyanate (TDI) in the propellant is taken as the detection object. To prepare the samples, groups are proportioned according to concentrations, grouped and then uniformly mixed; and a proper amount of the samples are selected and placed in a chromatographic bottle. A low-field nuclear magnetic resonance spectrometer is employed, and the detection conditions are selected. The changing curve of spin-spin relaxation time T2 with reaction time is detected, each vertical coordinate of the curve is normalized, and the reaction activity order of each component and TDI is acquired according to the speed of slope changes before the curve tends to be flat. The determination method provided by the invention has the advantages of simple operation, safety in experiments, reduction in cost, reliable experimental data, optimized detection conditions and simplified detection process.

Description

technical field [0001] The invention relates to a nuclear magnetic analysis method in the field of organic chemistry of aerospace fuel, in particular to a method for measuring the reactivity sequence of active hydrogen-containing components and curing agents in propellants. Background technique [0002] The Chinese journal "Solid Rocket Technology" in 2010, Volume 33, Issue 5 reported the document "Research on the Solidification Reaction Kinetics of Active Hydrogen Components in NEPE Propellants", which proposed to use the chemical titration method to determine the opposite ends at different temperatures. The reaction kinetic curves of the concentration of -NCO in the hydroxyl polyether (PEG) / phenylisocyanate (PI), bonding agent (NPBA) / PI, stabilizer (MNA) / PI system as a function of reaction time were calculated, and the corresponding system was calculated at Reaction rate constants and activation energies at different temperatures, by comparing the reaction rate constants a...

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Problems solved by technology

[0004] The above-mentioned published documents reflect the technical status of the determination method for the reactive sequence of the active hydrogen-containing component in the propellant and the curing agent. Its defects are: the operation process is cumbersome, the experiment requires reagents, the detection conditions are harsh, and the detection data can only be used indirectly. Compare

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