3,4-二硝基吡唑吸湿性研究OA

3,4-Dinitropyrazole(DNP)has a moderate melting point,high density,and excellent detonation performance,and is regarded as a promising carrier explosive for melt-cast formulations.However,DNP exhibits a certain degree of hygroscopicity under high-temperature and high-humidity conditions,which may adversely affect charge-processing operations and the final performance of explosive products.The hygroscopic behavior of DNP powder was investigated using the desiccator equilibrium method.The effects of post-treatment method,temperature,relative humidity,and particle size on moisture sorption were evalu-ated.The influence of moisture uptake on the thermal decomposition behavior of DNP was further examined,and quantum chemical calculations were performed to predict its key moisture-sorption sites.The results showed that the post-treatment meth-od had the most significant effect on the hygroscopicity of DNP,with benzene-recrystallized DNP exhibiting the lowest moisture sorption.Temperature and relative humidity had secondary effects,and the hygroscopicity of DNP increased with increasing tem-perature and relative humidity,whereas particle size had only a minor influence.When the ambient temperature was below 30℃,the critical relative humidity of DNP was higher than 84%,whereas it decreased to 75%at 40℃.Under the correspond-ing critical relative humidity conditions,the equilibrium moisture content of benzene-recrystallized DNP remained below 0.31%,with no obvious agglomeration or caking.Moreover,no significant changes were observed in the melting point or ther-mal decomposition temperature of DNP after moisture sorption.These results indicate that the hygroscopicity of DNP powder can be reduced through appropriate post-treatment and that moisture-related problems can be effectively prevented by control-ling the environmental temperature and relative humidity.Quantum chemical calculations further identified the H atom of the-NH group on the pyrazole ring as the key moisture-sorption site of DNP.