铜铬类催化剂对HTPE低易损推进剂燃烧性能的影响

摘要

采用差示扫描量热仪(DSC)研究了铜铬类燃速催化剂(亚铬酸铜CC01和铜铬复合氧化物CC02)对端羟基聚醚(HTPE)低易损推进剂中的高氯酸铵(AP)、改性硝酸铵(AN)、HTPE黏合剂体系热分解性能的影响.结果表明,加入少量的CC01和CC02均使AP高温分解峰温明显降低了16和29.7℃,AP高温分解活化能依次降低了16.65和22.59kJ/mol,均可提高AP的高温分解反应速率.CC01和CC02均使AN的热分解峰向低温方向依次前移了52.3和53.6℃,均降低了AN的分解活化能,使AN的热分解反应速率提高了3~4倍.CC01和CC02对HTPE黏合剂体系的热分解影响较小.在AP/AN/Al/HTPE低易损推进剂中,分别添加质量分数0.5%的CC01和CC02可显著提高HTPE低易损推进剂在3~15MPa下的燃速,可使推进剂在7MPa下的燃速分别提高34.1%和43.4%,但CC01和CC02对HTPE低易损推进剂在3~9MPa下的压强指数几乎无影响,而9~15MPa下的压强指数有所降低.%The effects of copper-chromium catalysts (the copper chromite CC01 and a Cu-Cr composite oxide CC02) on the thermal decomposition behaviors of ammonium perchlorate (AP),modified ammonium nitrate (AN) and HTPE binder for the low-vulnerability HTPE propellant were investigated by differential scanning calorimetry (DSC).It is found that the peak temperatures of AP high-temperature decomposition could be decreased by 16 and 29.7℃ after introducing small amounts of CC01 and CC02,respectively.In addition,the activation energies of this reaction step were also decreased by 16.65 and 22.59kJ/mol in the existence of CC01 and CC02,respectively.Thus,both CC01 and CC02 are able to enhance the high-temperature decomposition of AP.As for the modified AN,the decomposition temperatures were lowered by 52.3 and 53.6℃ by the addition of CC01 and CC02,respectively.Similar to AP,the corresponding activation energies of AN are decreased and the reaction rate constants are increased by 3-4 times.Nevertheless,CC01 and CC02 show little effects on the thermal decomposition of HTPE binder.Adding 0.5% of CC01 or CC02 to the AP/AN/Al/HTPE propellant obviously increases the burning rates at 3-15MPa.Especially,at 7MPa,CC01 and CC02 make the burning rates increase by 34.1% and 43.4%,respectively.On the other hand,CC01 and CC02 had little effect on the pressure exponent of low-vulnerability HTPE propellant under 3-9MPa,while they are effective in reducing the pressure exponent at 9-15MPa.