Rapid Detection Method Of Solvent Content In The Drying Process Of Three Base Propellant

Three-base gun propellant is a kind of gunpowder with nitrocellulose,nitroglycerin and nitroguanidine as its main components.It has the characteristics of high energy and low ablation,and is widely used in large-caliber artillery.During the drying process of three-base gun propellant,its solvent content needs to be detected.Aiming at the problem of large workload,long analysis time(more than two hours)of traditional solvent detection methods,and unable to meet the requirements for the continuous production process of three-base gun propellant,this paper studies the rapid detection of three-base gun propellant drying process by near infrared spectroscopy solvent content.The main research contents were as follows:Near-infrared spectroscopy was used to quickly detect three-base gun propellant alcohol and acetone solvent content before drying process.By comparing the value of root mean square cross-validation standard deviation(RMSECV),it was determined that the best pretreatment method for the alcohol and acetone solvent content component model was the second derivative,and the best modeling interval was 9403.2 to 4598.6cm^-1.The leave-one-out method was used for cross-validation to determine the number of main factors of the component model was 8.The cross-validation correlation coefficient(R_CV²)was 0.9870,the relative standard deviation(RPD)value was 8.8,and the prediction correlation coefficient(R_P²)was 0.9912.The average predicted relation deviation was 0.025%.The test results showed that the established alcohol and acetone solvent content component model was accurate and reliable,and the detection time was less than 1 minute,which could meet the rapid detection of alcohol and acetone solvent content of three-base gun propellant before drying process.Near-infrared spectroscopy was used to quickly detect the total volatility of three-base gun propellant after drying process.By comparing the value of RMSECV,the best pretreatment method for the component model was determined as the combination of first derivative+minus a straight line,and the best modeling interval was 7507.7 to 5447.4cm^-1.The leave-one-out method was used for cross-validation,and the main factor number of the component model was10,R_CV² was 0.9672,RPD was 5.65,R_P² was 0.9869,and the average value of the predicted relative deviation was 0.066%.The test results showed that the total volatility content model established was accurate and reliable,and the detection time was less than 1 minute,which could meet the rapid detection of the total volatility content of three-base gun propellant after drying process.An applied research on the rapid determination of total volatility of three-base gun propellant using the TTNIR-1700 near-infrared spectrometer was carried out.By comparing the value of RMSECV,the best pretreatment methods for the total volatility component model were determined as SNV and the combination of baseline correction+first derivative.The leave-one-out method was used for cross-validation to determine that the number of main factors of the component model were 12 and 14,R_CV² were 0.8998 and 0.8908,and the average prediction deviations of were 0.029%and 0.030%.The test results showed that the TTNIR-1700 near-infrared spectrometer was used to quickly determine the total volatilization content of three-base gun propellant.The established total volatility content component model was accurate and reliable,and the total volatility content of three-base gun propellant could be rapid detected in the drying process.