二茂铁类衍生物对HAN/PVA热分解影响研究

Effect of Ferrocene Derivatives on the Thermal Decomposition of HAN/PVA

为了解决硝酸羟铵/聚乙烯醇(HAN/PVA)的点火和燃烧困难问题,采用热重-差示扫描量热-红外光谱-质谱联用技术研究了HAN/PVA的热分解机理,并通过多重扫描速率的非等温法探索了卡托辛、乙基二茂铁、辛基二茂铁和叔丁基二茂铁等对HAN/PVA热分解性能的影响。结果表明,HAN/PVA的热分解主要发生在457.0~485.2K,失重73.7%,放热量为1312.1J/g,活化能Ea为88.8kJ/mol,在加热过程中固体样品基本转变成气态产物;本研究所用二茂铁类衍生物对HAN/PVA的热分解均具有明显的催化效果,催化作用由强到弱依次为叔丁基二茂铁、辛基二茂铁、卡托辛及乙基二茂铁,分别使HAN/PVA的热分解温度降低了42.9、27.5、17.5和12.3K;含辛基二茂铁、卡托辛和乙基二茂铁样品热分解反应的Ea分别为81.2、90.5和77.7kJ/mol;HAN/PVA/卡托辛样品热分解的Ea虽然最高,但指前因子A提高了2个数量级,反应速率常数大幅增加,催化效果最佳。

In order to increase the ignition and combustion performance of hydroxyl ammonium nitrate/polyvinyl alcohol(HAN/PVA),the thermal decomposition process of HAN/PVA was investigated by using simultaneous thermogravimetric analysis(TGA)-differential scanning calorimetry(DSC)-fourier transform infrared spectroscopy(FTIR)-mass spectrometry(MS),and the effect of catocene,ethylferrocene,octylferrocene and t-butylferrocene on the thermal decomposition of HAN/PVA was studied by multiple scanning methods.The results show that the decomposition process of HAN/PVA mainly occurs at 457.0-485.2K,with the mass loss,heat release and activation energy Ea of 73.7%,1312.1J/g and 88.8kJ/mol respectively,and the solid samples mostly decomposed into gaseous products.The four ferrocene derivatives have obvious catalytic effects on the thermal decomposition of HAN/PVA,and the descending order of the catalysts effects is as follows:t-butylferrocene,octylferrocene,catocene and ethylferrocene,which make the decomposition temperature decrease by 42.9,27.5,17.5 and 12.3K,respectively.The Ea of HAN/PVA thermal decomposition with octylferrocene,catocene and ethylferrocene are 81.2,90.5 and 77.7kJ/mol,respectively.The Ea of HAN/PVA/Catocene is the highest,however,the pre-exponential factor(A)increases 2 magnitudes,and the reaction rate constant greatly increased,leading to the best catalytic effect induced by catocene.