2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4,3,0]壬酮-8的放热分解反应动力学

在程序升温条件下,用DSC研究了2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4,3,0]壬酮-8的放热分解反应动力学参数.表明该反应的微分形式的动力学模式函数、表观活化能(Ea)和指前因子(A)分别为3(1-α)[-ln(1-α)](2)/(3), 204.7 kJ/mol 和 1020.89 s-1.该化合物的热爆炸临界温度为188.81℃.反应的活化熵(ΔS≠)、活化焓(ΔH≠)和活化自由能(ΔG≠)分别为141.6 J/(mol*K), 200.9 kJ/mol 和136.8 kJ/mol.     

以温度为函数的硝仿系炸药的爆发分解反应动力学参数

用爆发点试验装置测定了6种硝仿系炸药:2,2,2-三硝基乙基-N-硝基-甲胺(TNMA)、二(2,2,2-三硝基乙基-N-硝基)乙二胺(BTNEDA)、4,4,4-三硝基丁酸-2,2,2-三硝基乙酯(TNETB)、二(2,2,2-三硝基乙醇)缩甲醛(BTNF)、1,1,1,3-四硝基丙烷(TETNP)和二(2,2,2-三硝基乙基)硝胺(BTNNA)在不同温度下的爆发延滞期.依据谢苗诺夫方程lnt_(lag,i)=E_α/RT_i-lnA_α,由lnt_(lag,i)对1/T_i的关系,用作图法和最小二乘法计算了爆发分解反应的表观活化能(E_α)、指前因子(A_α)和5 s爆发点.用非线性等转化率积分法所得的表观活化能(E_α)校验了由lnt_(lag,i)～1/_Ti关系得到的Eα值.借助热力学关系式,计算了爆发分解反应的活化热力学参数[活化自由能(ΔG≠),活化焓(ΔH≠)和活化熵(ΔS≠)].结果表明: (1) E_α和作图法所得E_α间的相对误差在±5%以内; (2) E_α与最小二乘法所得E_α相等的事实佐证了不同温度下爆发分解反应延滞期内的分解深度是相等的,所得E_α和A_α值是可接受的,谢苗诺夫方程推导过程中采用A_α>>G(α)的假设是合理的; (3) 以5 s爆发点和ΔG~#为判据,6种硝仿系炸药对热抵抗能力的次序为:TNETB＞BTNF＞BTNEDA＞TETNP＞TNMA＞BTNNA.     

1，4，6，6-四硝基-1，4-二氮杂环庚烷的制备及性质

:2 ,2 -二硝基 - 1,3-丙二醇与乙二胺进行曼尼希缩合反应 ,生成 3,3,7,7-四硝基 - 1,5 -二氮杂双环 [3.3.2 ]癸烷 ( ) ,该中间体 用硝酸 -五氧化二磷混合物硝化 ,得到 1,4,6 ,6 -四硝基 - 1,4-二氮杂环庚烷 ( )。对 的物理性质、热稳定性及爆炸性质进行了初步的研究。     

TEX色谱分析条件的建立及热稳定性研究

为研究4,10-二硝基-2,6,8,12-四氧杂-4,10-二氮杂四环[5.5.0.05,903,11]十二烷(TEX)的稳定性,建立了TEX的高效液相色谱(HPLC)分析方法,采用TG-DTG和DSC研究了TEX的热行为,测定了不同升温速率(5、10、15、20和25K/min)下TEX的分解峰温,用Kissinger方法计算了TEX放热分解反应的表观活化能(Ek)和指前因子(A),用热力学方程计算了TEX放热分解反应的活化熵(△S≠)、活化焓(△H≠)和活化吉布斯自由能(△G≠)。结果表明,TEX对热较稳定,其热分解反应的△S≠、△H≠和△G≠值分别为501.03J/(K·mol)、432.48kJ/mol、145.26kJ/mol。     

DPT和DNPT与液体四氧化二氮的反应

本文报道了1,5-二硝基五亚甲基四胺(DPT)与液体四氧化二氮(N_2O_4)反应。在没有溶剂情况下,生成1,5-二硝基-3,7-二亚硝基-1,3,5,7-四氮杂环辛烷(DNDS)——乌洛托品(HA)合成HMX的中间体;当乙腈溶剂存在时,则生成1,3,5-三硝基-7-亚硝基-1,3,5,7-四氮杂环辛烷(MNX)和1,3,5,7-四硝基-1,3,5,7-四氮杂环辛烷(HMX)两种产品。1,5-二亚硝基五亚甲基四胺(DNPT)在相同条件下生成乌洛托品二硝酸盐(HADN)。DNDS和MNX在存放过程中均能部分地转化为MNX和HMX,即N-亚硝基在空气中能转化成N-硝基。     

DPT和DNPT与液体四氧化二氮的反应

本文报道了1,5-二硝基五亚甲基四胺(DPT)与液体四氧化二氮(N_2O_4)反应。在没有溶剂情况下,生成1,5-二硝基-3,7-二亚硝基-1,3,5,7-四氮杂环辛烷(DNDS)——乌洛托品(HA)合成HMX的中间体;当乙腈溶剂存在时,则生成1,3,5-三硝基-7-亚硝基-1,3,5,7-四氮杂环辛烷(MNX)和1,3,5,7-四硝基-1,3,5,7-四氮杂环辛烷(HMX)两种产品。1,5-二亚硝基五亚甲基四胺(DNPT)在相同条件下生成乌洛托品二硝酸盐(HADN)。DNDS和MNX在存放过程中均能部分地转化为MNX和HMX,即N-亚硝基在空气中能转化成N-硝基。     

1,1′-二甲基-5,5′-偶氮四唑一水合物的放热分解反应动力学

在程序升温条件下,用DSC研究了1,1′-二甲基-5,5′-偶氮四唑一水合物的放热分解反应动力学参数.表明该反应的微分形式的经验动力学模式函数,表观活化能(Ea)和指前因子(A)分别为(1-α)-1.53, 114.1 kJ/mol和108.72 s-1.该化合物的热爆炸临界温度为215.45 ℃.     

柠檬酸铈的热分解机理及反应动力学

在程序升温条件下,用DSC、TG/DTG、固相原位反应池/FTIR联用技术,研究了柠檬酸铈的热行为、分解机理和常压非等温分解反应动力学参数,获得了相应的动力学方程.结果表明,柠檬酸铈的热分解反应存在1个脱水吸热阶段(Stage Ⅰ)和2个放热阶段(Stage Ⅱ和Ⅲ);主放热分解阶段(Stage Ⅱ)的表观活化能Ea和指前因子A分别为148.59kJ/mol和1011.64s-1;动力学方程可表示为:dα/dt=1011.81(1-α)[-ln(1-α)]1/3e-1.79×104/T;反应机理服从n=2/3的Avrami-Erofeev方程.由加热速率β→0的DSC曲线的初始温度(Te)和峰温(Tp)计算得柠檬酸铈的热爆炸临界温度值Tbc和Tbp分别为527.09K和542.71K.反应的△S≠、△H≠和△G≠分别为:16.82J·mol-1·K-1、163.11kJ/mol和158.74kJ/mol.     

二维核磁共振及其在硝基化合物分析中应用

本文简述二维核磁共振(包括同核、异核2D-J 分解谱;异核2D-相关谱;同核2D-cosy、cosy-45、远程 cosy、接力 cosy 等相关谱)原理、实验方法,并用于3,4-二硝基甲苯、1,4-二硝基-2,3,5,6-四乙酰氧基环己烷、2,2′,4,4′-四硝基二苯硫醚和2,5,7-三硝基-9-(2′,2′,2′-三硝基乙基)2,5,7,9-四氮杂双环[4.3.0]壬酮8等硝基化合物的结构分析。     

VNS反应合成LLM-116

以1,3-二硝基吡唑为原料,经热重排、氨气中和得到3,5-二硝基吡唑铵盐,然后酸化得到3,5-二硝基吡唑.以三甲基肼碘化物(TMHI)作为异常亲核取代氢(VNS)反应试剂,与3,5-二硝基吡唑在叔丁醇钾为催化剂,利用VNS反应合成4-氨基-3,5-二硝基吡唑(LLM-116).采用红外分析、核磁共振、元素分析等仪器鉴定了其结构,讨论了VNS反应机理及影响因素.通过实验,得出最佳VNS反应试剂为TMHI,反应时间为4 h,反应温度为25 ℃,收率达到60%.     

四硝基并哌嗪的催化热分解及机理研究

采用高压差示扫描量热法(PDSC)、热重分析法(TGA)和快速扫描傅里叶变换红外光谱法(FT-IR),研究了四硝基并哌嗪(TNAD)的热分解机理,并采用FT-IR技术和TG/MS(质谱)联用分析了TNAD热分解过程的凝聚相变化,确认其热分解机理与化学反应过程。研究表明,在1MPa压力下TNAD的分解过程较简单,无熔融吸热峰出现,属固相分解,主要放热峰出现在212.5～251.7℃。NTO-Pb、TNAD/φ-Pb、β-Cu和AD-Cu等铅铜盐对TNAD的催化作用明显,都能使其热分解反应提前,相比之下,β-Cu和NTO-Pb催化效果更好。炭黑、Al_2O_3、Al等添加剂对TNAD起到稀释作用,缓和了分解放热过程,可起到稳定燃烧的作用。TNAD热分解主要有2个历程,分解过程中产生的主要气体产物为HCHO、NO、HCN和-C2_H_2、-CHO等碎片离子。     

Thermal Behavior and Thermolysis Kinetics of the Explosive Trans‐1,4,5,8‐Tetranitro‐1,4,5,8‐Tetraazadecalin (TNAD)

Trans‐1,4,5,8‐Tetranitro‐1,4,5,8‐Tetraazadecalin (TNAD), a cyclic nitroamine, has been studied with regard to the kinetics and mechanism of thermal decomposition, using thermogravimetry (TG), IR spectroscopy, and pressure differential scanning calorimetry (PDSC). The IR spectra of TNAD have also been recorded, and the kinetics of thermolysis has been followed by non‐isothermal TG. The activation energy of the solid‐state process was determined by using the Flynn‐Wall‐Ozawa method. Compared with the activation energy obtained from the Ozawa method, the reaction mechanism of the exothermic process of TNAD was classified by the Coats‐Redfern method as a nucleation and nuclear growth (Avrami equation 1) chemical reaction (α=0.30–0.60) and a 2D diffusion (Valensi equation) chemical reaction (α=0.60–0.90). E_a and ln A were established to be 330.14 kJ mol⁻¹ and 29.93 (α=0.30–0.60) or 250.30 kJ mol⁻¹ and 21.62 (α=0.60–0.90).     

2,4-二氰基和2,4-二硝基五环[4.3.0.0^2,5.0^3,8.0^4.7]壬烷的热行为

在线性升温条件下，用ＳＣ－ＤＳＣ研究了２，４－二氯基五环［４．３．０．０＾２，５．０＾３，８．０＾４，７］壬烷（ＤＣＰＣＮ）和２，４－二硝基五环［４．３．０．０＾２，５．０＾２，８．０＾４，７］壬烷（ＤＮＰＣＮ）的热行为。在我们的实验条件下，未检测到ＤＣＰＣＮ的熔化吸热峰，因此未得到ＤＣＰＣＮ的熔化过程热力学参数。测定了升温速率为零时，ＤＣＰＣＮ和ＤＮＰＣＮ放热分解反应的外推始点温度、峰温以及自发     

A DSC Study on the Effect of RDX and HMX on the Thermal Decomposition of Phase Stabilized Ammonium Nitrate

Phase stabilized ammonium nitrate(PSAN) was prepared by incorporating copper(II) diammine nitrate in the ammonium nitrate(AN) crystal lattice. The effect of two energetic materials viz., RDX and HMX on the thermal decomposition of PSAN was investigated using DSC. The decomposition temperatures of PSAN and RDX are almost in the same temperature range. The decomposition of PSAN is endothermic and that of RDX is exothermic, while that of a 1:1 mixture of the two is exothermic with a net heat release in excess of that of the individual reactions, which is attributed to the combustion reaction among the decomposition products of PSAN and RDX. Though HMX decomposes at a higher temperature, in presence of molten PSAN a substantial portion of it decomposes at a lower temperature along with PSAN with a net excess heat release, again due to the combustion reaction. The kinetic parameters of the two exothermic decompositions were computed using two equations based on variable heating rate method viz., Kissinger and Ozawa equations. The activation energy obtained from Ozawa method was refined by an iteration procedure. There is a close agreement among the values obtained by the three methods. The kinetic parameters for PSAN-HMX mixture are lower, probably due to the effect of its higher heat release.     

Kinetics of the curing reaction of unsaturated polyester resins catalyzed with new initiators and a promoter

In this article, the curing of unsaturated polyester resins catalyzed with a promoter [cobalt(II) octoate] and free‐radical initiators is presented. The new initiators were formed by the oxidation process of ethyl methyl ketone or cyclohexanone with hydrogen peroxide and the mixture of solvents containing hydroxyl groups. As a reference, a typical curing system containing ethyl methyl ketone hydroperoxide (Luperox) and the promoter was used. The differential scanning calorimetry runs were performed at different heating rates. The experimental data were fitted with the empirical kinetic model. First, the kinetic parameters (activation energy, frequency factor, and reaction order) were obtained with a single reactive process and with the nth‐order reaction f(α), the nth‐order reaction f(α) with autocatalysis, and the first‐order reaction f(α) with autocatalysis. Second, two or three different reactive processes with the nth‐order reaction f(α) for each step were used. The obtained values of the activation energies for the curing of the unsaturated polyester resins with the free radical initiator–cobalt(II) salt catalytic system were in the range 40–60 kJ/mol for the polymerization initiated by the redox decomposition of the initiators and 80–90 kJ/mol for the polymerization initiated by the thermal decomposition of the initiators at high temperatures. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1870–1876, 2006     

苯氨基甲酸甲酯热解制备苯基异氰酸酯的非等温动力学

采用热分析与红外联用技术对苯氨基甲酸甲酯(MPC)热解历程进行分析,结果表明,苯氨基甲酸甲酯的热解过程是一步生成苯基异氰酸酯同时释放出甲醇气体. 进一步对该热解反应进行了非等温动力学研究,对MPC的热解数据采用Flynn-Wall-Ozawa法计算得到反应活化能. 采用5种方法考察反应动力学参数,结果表明,MPC热解机理为相边界反应模型,机理函数为G(a)=a1/3,热解反应活化能E=20.52 kJ/mol,指前因子lgA=2.23,动力学方程为a1/3= 169.82exp[20.52′103/(8.314T)]t.     

菱镁矿热分解的动力学研究

利用热重(TG)分析法,对不同粒度菱镁矿的热分解过程进行研究.根据Flynn-Wall-Ozawa法,拟合计算得到不同粒度菱镁矿热分解的活化能和指前因子.采用Thermo-kinetics软件对可能性最大的5种动力学机理函数进行拟合,根据相关系数最大的原则确定最佳分解机理.研究结果表明:菱镁矿热分解的活化能随菱镁矿粒度的增大而减小,当菱镁矿的粒度由小增大时,控制其热分解过程的机理由化学反应逐渐向颗粒内部的传热和CO2的扩散传质转变;其热分解过程的最可几机理函数为R3模型,即三级相边界扩散反应,函数方程为G(α)=1-(1-α)1/3.     

一种判定RDX热分解机理函数与热安全性的方法

将DSC、TG数据与Malek法相结合研究了RDX的热分解,得到外延起始温度Le0、拐点温度T、峰顶温度Tp、分解终止温度Tf、分解焓变ΔH、表观活化能E、指前因子A、反应级数n、热爆炸临界温度Tb和自加速分解温度TSADT;利用TG热分析得到RDX热分解的起始分解温度T0、质量损失Δm%、最大质量损失速率及对应的温度...