Research On Precise Synthesis Method Of Azoles Energetic Materials Based On Online Infrared Spectroscopy

With the concept of green chemistry such as eco-environmental friendliness and sustainable economic and social development,which will profoundly affect the development of major changes in chemical manufacturing and related industries in the future,research on new material synthesis strategies can maximize chemical transformation and precise and efficient synthesis.Energetic Material has the advantages of small volume,high density,low inertness and high energy.The azole nitrogen-containing heterocyclic compound has been widely used due to its advantages such as high heat of generation,easy realization of oxygen balance,easy introduction of various groups,and environmental protection.Therefore,research on the synthesis reaction of typical energetic materials is of great practical significance to achieve accurate synthesis,process optimization and performance estimation of energetic materials.The full text consists of four chapters,the main contents are:（1）Based on 3,5-diamino-1,2,4-triazole（DAT）as the research basis,the optimal synthetic process of DAT for nitrogen compounds was determined.First,the target product DAT was synthesized using dicyandiamide and hydrazine hydrochloride as starting materials,and then the effects of different reaction synthesis conditions（solvent,material ratio,temperature,reaction time,pH and extraction solvent）on the yield and purity of DAT synthesis were investigated.Studies have shown that the optimal DAT synthesis reaction conditions are:water as the solvent,the reaction temperature of 48℃⁵0℃,the reaction time of 180min,the OH^-equivalent of 1.9eq,and the methanol-isopropanol mixed purification solvent.Finally,under the optimal synthetic route conditions,the optimal synthetic process conditions of the azole nitrogen compound DAT were established.Compared with traditional synthesis methods,the yield of DAT obtained by this process is greater than 90%,and the purity is greater than99%,and better quality and appearance can be obtained.This research provides new ideas for the optimization of energetic material synthesis process.（2）Based on the synthetic reaction process of DAT,an on-line ATR-IR spectroscopy technique and an SIMPLISMA method were established.Monitoring of synthetic reactions and analytical methods of active intermediates.Firstly,the infrared spectrum of the synthesis reaction process was pre-processed by WT,and then the number of active intermediates in the synthesis reaction system was determined by PCA and SCM.Secondly,the infrared spectrum of the entire synthesis reaction process was analyzed by SIMPLISMA method,and the concentration change curve of each component of the synthesis reaction system and the pure infrared spectrum of the active intermediate were obtained,and then the molecular structural formulas of the two active intermediates were obtained.Finally,the DFT simulation calculation was used to optimize the geometric configuration and vibration frequency of the intermediate,which further verified the rationality of the analysis of the active intermediate.Studies have shown that online ATR-IR combined with SIMPLISMA can successfully analyze the active intermediates of DAT synthesis system,and then infer the mechanism of DAT synthesis reaction.This research provides research ideas and technical support for the optimization of new energetic materials synthesis process and green synthesis.（3）Based on the performance prediction of nitrogen-containing compounds,a prediction method for density performance of nitrogen-containing compounds based on random forest combined structure-activity relationship was established.Firstly,the molecular descriptors of nitrogenous compounds and their corresponding density performance parameters were collected,and the effects of different pretreatment methods on the pretreatment effect of the original molecular descriptors of nitrogenous compounds were investigated.Then,the variable importance of the RF algorithm is used to perform feature molecular descriptor screening and optimization research,and the RF variable importance threshold parameters are optimized.Based on the optimized pretreatment method,characteristic molecular descriptors and model parameters,a random forest-structure-activity relationship model based on the prediction of nitrogen compound density performance was constructed,and the density performance of nitrogen compounds in the test set was predicted.Studies have shown that the WT-RF structure-activity relationship model can obtain better prediction performance and can more accurately predict the density performance of nitrogen compounds.Its correction set R²_CV is0.8846,RMSECV is 0.1061%,prediction set R_P² is 0.9724,and RMSEP is 0.0884%.Compared with traditional experimental testing methods,this method has the advantages of fast analysis speed,accurate prediction results,and short monitoring period.This research provides new ideas and methods for the prediction of the performance of energetic compounds and the design of new energetic materials.