四硝基甘脲的合成工艺改进及热分析  

Modified Synthesis and Thermal Analysis of Tetranitroglycoluril

作　　者：郑志花[1] 王建龙[1] 李永祥[1] 王艳红[1] 曹端林[1] 

机构地区：[1]中北大学化工与环境学院,山西太原030051

出　　处：《含能材料》2015年第5期438-442,共5页Chinese Journal of Energetic Materials

基　　金：中北大学研究生科技基金资助(20131034)

摘　　要：以尿素和乙二醛为原料,在盐酸催化下经微波加热制得甘脲（GU）,用发烟硝酸醋酐对GU硝化合成了四硝基甘脲（TNGU）。考察了反应温度、反应时间和发烟硝酸用量等对硝化反应过程的影响。采用红外光谱、核磁共振光谱及元素分析对TNGU结构进行了表征,用DSC对其进行了热分析,用Kissger和Ozawa法确定了TNGU的反应动力学参数,估算了热爆炸临界温度（Tb）及热分解反应的活化熵变（ΔS≠）、活化函变（ΔH≠）和活化吉布斯自由能变化值（ΔG≠）。结果表明,TNGU的较佳合成工艺条件为：GU5g时,发烟硝酸70mL,醋酸酐35mL,反应温度25～30℃,反应时间4h,TNGU收率为84%（以GU计）。此工艺较文献废酸液量减少30mL,硝化时缩短4h。TNGU的Tb为465.34K,ΔS≠、ΔH≠和ΔG≠分别为171.46J·mol-1、195.00kJ·mol-1和194.99kJ·mol-1,TNGU的热分解为放热熵增的过程。Glycocluril （GU） was prepared in the presence of hydrochloric acid by microwave heating with urea and glyoxal as raw materials. Through fuming nitric acid and acetic anhydride, tetranitroglycoluril （TNGU） was synthesized from nitration of GU. The effects of reaction temperature, reaction time and dosage of fuming nitric acid on the nitration were investigated. The structure of TNGU was characterized by IR, 1H NMR, 13C NMR and elemental analysis. Thermal analysis of TNGU was studied by DSC, and thermal decomposition kinetics parameters such as EK, A and Eo were respectively calculated with Kissinger and Ozawa, and EK and Eo were significantly consistent. The critical temperature of thermal explosion （Tb）, the entropy of activation （ΔS≠）, enthalpy of activation （ΔH≠） and free energy of activation （ΔG≠） of thermal decomposition were calculated. Results show that the optimal technological conditions for synthesizing TNGU were as follows： urea 5 g, fuming nitric acid 70 mL and acetic anhydride 35 mL, reaction temperature between 25~30 ℃, reaction time 4 h, the yield of tetranitroglycoluril was 84% （according to GU）. Under these conditions, the amount of waste acid was 30 mL, less than that in literature, and nitration time was shortened by 4hs. Tb of TNGU is 465.34 K, and its ΔS≠,ΔH≠ and ΔG≠ are 171.46 J·mol-1, 195.00 kJ·mol-1 and 194.99kJ·mol-1 respectively. The thermal decomposition of TNGU was exothermic with increasing entropy.

关 键 词：含能材料 四硝基甘脲 甘脲 硝化 热分解 

分 类 号：TQ560.1[化学工程—炸药化工]