降低阻燃剂四溴苯酐中游离硫酸的方法研究

通过剖析四溴苯酐中游离硫酸形成原因,对原有的生产工艺进行优化改进,合成得到了熔点高、游离硫酸含量低的四溴苯酐。     

科聚亚提高四溴苯酐二醇阻燃剂价格

科聚亚公司2007年3月9日宣布其四溴苯酐二醇(PHT4-diol)阻燃剂产品的价格将提高5%,并将于2007年4月1日起在合同允许范围内生效。     

阻燃剂聚丙烯酸五溴苄基酯的热分解动力学

用热分析法研究了阻燃剂聚丙烯酸五溴苄基酯在空气和氮气气氛中的热分解动力学。该阻燃剂在空气气氛中为两步分解,在氮气气氛中为一步分解,利用Friedman法求出聚丙烯五溴苄基酯的第一步分解反应的活化能变化趋势,同时利用Satava-Sestak法研究了其热分解机理。结果表明,在0.10至0.90的转化率范围内,聚丙烯酸五溴苄基酯在空气气氛下的活化能为167.35kJ/mol,在氮气气氛下的活化能为171.94kJ/mol,热分解机理均为Avrami-Erofeev方程,随机成核和随后生长,反应级数分别为n=23和n=12。动力学方程分别为G(a)=[-ln(1-a)]23和G(a)=[-ln(1-a)]12。     

科聚亚提高四溴苯酐二醇阻燃剂价格

美国康涅狄格州Middlebury，2007年3月9日——科聚亚公司（纽约证券交易所代码：CEM）宣布其四溴苯酐二醇（PHT4dio1）阻燃剂产品的价格将提高5％，并于2007年4月1日起在合同允许范围内生效。     

碳酸氢钠热分解的动力学模型与研究

加热分解碳酸氢钠制备碳酸纳和二氧化碳气,属于气、固两相同的非均相反应。本文在对该反应机理进行了分析的基础上,认为此反应的动力学过程应为化学反应控制。应符合化学反应控制的动力学模型,实验证明:当温度为448K时,所得数据可与所应用的模型吻合。     

黑索今基发射药热分解动力学研究

利用失重法(TG)在升温速率5 K·min~(-1)、10 K·min~(-1)、20 K·min~(-1)下对RDX基发射药的热分解进行了测试,并对其热分解动力学进行了研究。实验结果表明:将TG数据与Malek法相结合,利用辅助函数y(α)和z(α)判定RDX基发射药热分解动力学机理函数,通过动力学表达式的求解可以得出两种不同配方发射药的表观活化能及反应级数。     

结合胶的热分解反应动力学研究

应用TG/DSC技术研究了天然橡胶(NR)和以普通炭黑、碳纳米管(MWNT)分别作为填料制备的结合橡胶。应用FWO(Ozawa-Flynn-Wall)计算了NR、炭黑结合胶及MWNT结合胶的热分解动力学,并利用多元非线性拟合法求得NR、炭黑结合胶及MWNT结合胶的热分解反应机理及机理函数。     

四溴苯酐合成新方法研究

介绍一种以邻二甲苯为原料,经苯环溴化、侧链溴化、酯化、水解、氧化、脱羧制取有机阻燃剂四溴苯酐的合成新方法,产物总收率为76．0％,HPLC法测得含量达98．3％。合成过程采用溴素回收,降低了生产成本,明显改善了操作条件,消除了传统方法对环境的污染。     

膨化硝酸铵的热分解动力学研究

利用热重法测得了普通工业硝酸铵和膨胀化硝酸铵的热重曲线,计算到了普通肖酸铵和膨化硝酸铵的热分解活化能,研究了普通工业硝酸铵和膨化硝酸铵的热分解反应机理和动力学方程。     

Chemical Kinetics of the Thermal Decomposition of NTO

The kinetics of thermal decomposition of 3‐nitro‐2,4‐dihydro‐3H‐1,2,4‐triazol‐5‐one (NTO) in the temperature interval from 200 °C to 260 °C was investigated using a glass Bourdon gauge. The overall decomposition reaction includes two distinct stages: the fast first‐order decomposition and the subsequent autocatalytic reaction. The importance of the first stage increases with increasing decomposition temperature and decreasing loading density of the Bourdon gauge (m/V). A period of preliminary heating, at a lower temperature, strongly influences the autocatalytic stage when the decomposition is carried out at a higher temperature. In the temperature domain 200–220 °C, the Arrhenius constants of the decomposition reaction are found to be close to the values usually observed for nitrocompounds: E=173 kJ/mol and log₁₀ k≈12.5 (s⁻¹). It is shown that a simple model of NTO decomposition based on an autocatalytic reaction of the m‐th order can describe the course of the decomposition at high temperature but the m number appears to be excessively high, up to 4. A new model of the decomposition is developed, including an initial monomolecular reaction, decomposition of the crystalline substance, and an autocatalytic reaction of NTO dissolved in liquid decomposition products. This model gives the common order of autocatalysis, m=1.     

全氟丁基磺酸钾阻燃PC热分解动力学研究

采用Kissinger法、Friedman法和Flynn-Wall-Ozawa法三种动力学方法研究了全氟丁基磺酸钾（PPFBS）阻燃聚碳酸酯（PC）体系的热分解动力学。由这三种方法计算得到的动力学参数十分吻合,表明PPFBS的加入使PC热分解活化能提高,改变了PC的热分解途径,提高了PC的阻燃性能。     

聚酰胺固化环氧树脂的热分解动力学研究

利用热重分析(TG)采用不同升温速率(10,15,20,25℃/min)分别在空气和氮气气氛下对聚酰胺固化环氧树脂热稳定性进行了研究.采用Coats-Redfem和Ozawa热分析处理动力学数据的方法,计算了环氧树脂热分解反应活化能E、反应级数n及频率因子A.求得空气气氛下5%～30%的失重率下反应表观活化能在70.3...     

纳米粒子的热分解动力学模型

研究了纳米粒子热分解反应的动力学规律,首次提出了纳米粒子热分解的通用的微分速率方程,导出了纳米粒子热分解通用的动力学微分机理函数;并且用纳米碳酸钙、纳米碳酸锌和纳米氢氧化铜的热分解数据考察了机理函数的适用性.研究结果表明3种纳米粒子热分解过程具有相似的动力学规律和相同的机理函数,其速率方程与纳米粒子瞬时表而积分数的幂成正比,其机型函数为纳米粒子剩余质量分数的2n/3次方.     

I_2-AlCl_3催化合成四溴苯酐的工艺研究

针对国内四溴苯酐生产现状,在对溴化反应过程机理分析的基础上,对反应过程进行优化,得到了较优的反应条件及操作过程:以I2、AlCl3作为反应的复合催化剂,用量为苯酐的2%,采用分段控温缓慢加溴的操作方式,最高反应温度140℃,反应时间5￣6h,四溴苯酐的收率为96%,熔点276.3￣277.2℃,硫酸含量0.13%。     

Experimental Investigation on the Heterogeneous Kinetic Process of the Low Thermal Decomposition of Ammonium Perchlorate Particles

The thermal decomposition of ammonium perchlorate has been extensively studied in the past. Nevertheless, the various results published illustrate, on the one hand, significant differences regarding the influence of different parameters on the decomposition and on the other hand, a lack of useful quantitative laws to predict the thermal behaviour of this crystal under a range of conditions (temperature, duration of exposure, presence of confinement).     

An Investigation on Thermal Decomposition of DNTF‐CMDB Propellants

The thermal decomposition of DNTF‐CMDB propellants was investigated by pressure differential scanning calorimetry (PDSC) and thermogravimetry (TG). The results show that there is only one decomposition peak on DSC curves, because the decomposition peak of DNTF cannot be separated from that of the NC/NG binder. The decomposition of DNTF can be obviously accelerated by the decomposition products of the NC/NG binder. The kinetic parameters of thermal decompositions for four DNTF‐CMDB propellants at 6 MPa were obtained by the Kissinger method. It is found that the reaction rate decreases with increasing content of DNTF.     

Experimental Study of Methane Hydrate Decomposition Kinetics

Experimental investigations of methane hydrate dissociation kinetics were performed. The test rig consists of a stirred reactor equipped with particle size analysis. The observed dissociation rates were found to be about one order of magnitude faster than previously reported by others. A mass transfer control of the dissociation process is proposed to dominate in the proximity of a dispersed hydrate‐liquid interface. The results are relevant for the design of processes employing dispersed gas hydrates in chemical engineering and the production of natural gas from dispersed deposits.     

Kinetics of Ozone Decomposition in Water

The kinetics of ozone decomposition in water were determined experimentally over a pH range of 0.45 to 10.2 and temperature range of 3.5 to 60°C in a batch reactor. These data were analyzed and compared with th e reanalyzed data from other investigators.     

聚苯乙烯热分解反应动力学研究

采用热重法对聚苯乙烯(PS进)行了热分解动力学研究。结果表明:PS呈两段热解,主要发生在340~520℃区间,在该范围内,PS在400~444℃达到最大热解速率;随着升温速率的增加,其最大热解速率对应的峰温有所升高,热解起始、终止温度也相应提高,但最终质量分数基本一致,为4.4%~4.8%。采用等转化率法和比较法求解得到PS热解过程的动力学三因子,其活化能为136.76kJ/mol,指前因子lnA为26~28,动力学机理函数的积分形式为。用反应模型对实验数据进行了模拟,模拟准确度很高,标准偏差为0.048。