PA6T的非等温结晶动力学

采用示差扫描量热仪(DSC)考察了PA6T的非等温熔融结晶过程,分别采用Avrami方程、Ozawa方程及Mo提出的新方程对PA6T的非等温动力学数据进行比较分析,计算了相关非等温结晶动力学参数和非等温结晶活化能。结果表明:对于PA6T,用Mo法处理得到的结果更理想。     

聚醚醚酮酮等温结晶动力学的研究

聚醚醚酮酮等温结晶动力学的研究陈艳，王军佐，曹俊奎，那辉，吴忠文（吉林大学化学系，长春，１３００２３）关键词聚醚醚酮酮，等温结晶动力学，差示扫描量热法聚醚醚酮酮（ＰＥＥＫＫ）是在聚醚醚酮（ＰＥＥＫ）基础上开发成功的一种耐热高分子材料。它保持了ＰＥＥＫ...     

热致液晶聚酯酰亚胺的非等温相转变动力学研究

以差示扫描量热法对热致液晶聚酯酰亚胺的结晶过程和液晶化过程的非等温相转变动力学行为进行了初步研究，根据Ｊｅｚｉｏｒｎｙ方法处理数据得到了表征聚合物非等温相转变动力参数Ｚｃ，Ｇｃ并对其进行了讨论，结果表明，在所研究的条件下聚合物的相转变过程基本上符事Ｊｅｚｉｏｒｎｙ结论，但两种相转变的成核与生长方式是不同的。     

己内酯和2,2-二羟甲基丁酸共聚酯的非等温结晶动力学研究

采用示差扫描量热仪(DSC) 研究了具有生物相容性及可降解性P(BHB-CL)超支化共聚酯的非等温熔融结晶过程, 分别采用Avrami 方程、Ozawa 方程和Mo方程对P(BHB-CL)共聚酯的非等温动力学数据进行比较分析, 计算了相关的非等温结晶动力学参数, 并利用Kissinger方程计算其非等温结晶活化能. 结果表明, Mo方程更适合描述P(BHB-CL)共聚酯的非等温结晶过程.     

含CL-20的改性双基推进剂的热行为及非等温反应动力学

用DSC和TG方法研究了含六硝基六氮杂异伍兹烷(CL-20)的改性双基推进剂在常压(0.1 MPa)和高压(4和7 MPa)下的热行为和高压下的热分解反应动力学. 结果表明, 该推进剂常压下DSC曲线有3个放热峰, 相应TG曲线有3个失重过程; 而高压下DSC曲线只有一个放热峰, 高压下放热峰的峰温随加热速率增大而升高. 高压下该推进剂放热分解反应机理和反应动力学参数受测试环境压强影响较弱, 反应机理是随机成核和随后生长, 放热分解反应的动力学方程可以表示为, 4 MPa时, dα/dt=1014.5(1-α)[-ln(1-α)]1/3e-17981.7/T; 7 MPa时, dα/dt=1014.7(1-α)·[-ln(1-α)]1/3e-18138.1/T.     

超支化聚酯对聚乙二醇非等温结晶行为的影响

利用差示扫描量热法(DSC)、偏光显微镜(POM)以及傅里叶变换红外(FTIR)光谱研究了一种超支化聚酯(HBP)对聚乙二醇(PEG)非等温结晶行为的影响,用Ozawa法、Jeziorny法和莫志深法对非等温结晶动力学进行了分析.结果表明:PEG和HBP/PEG的非等温结晶过程可用Ozawa和莫志深动力学方程描述,与Jeziorny动力学方程不符;超支化聚酯的加入改变了PEG的结晶成核和生长机理,对PEG的结晶有一定的延缓作用.超支化聚酯中的羰基与PEG的端羟基形成的氢键以及超支化聚酯自身较大的分子体积和高度支化的结构所导致的位阻效应是超支化聚酯延缓PEG结晶的主要原因.     

非共价键合杂化体系中聚己内酯的非等温结晶动力学

非共价键合杂化体系中聚己内酯的非等温结晶动力学;聚己内酯;有机-无机杂化材料;差示扫描量热法;非等温结晶动力学     

PA13N的合成和非等温结晶动力学研究

采用DSC方法研究了PA13N在不同降温速率下的结晶过程,并利用Avrami方程研究了其非等温结晶动力学。在非等温结晶过程中,随着降温速率的增大,结晶温度向低温偏移。综合利用Avrami方程得到Avrami指数为1.35~1.88和结晶速率常数Zc≈1;并求得其结晶活化能为-58.42kJ/mol。结果表明,PA13N的结晶能力小于其他脂肪族尼龙。     

非等温液-固相酯化反应动力学研究

根据稀土盐催化剂催化的乙二醇单乙醚醋酸酯的液相合成反应的特点,导出了非等温变体积条件下的反应速率方程,并提出了利用一条实验曲线,计算动力学参数的动态方法、以此为基础,对不同实验条件下的多组实验数据进行了动力学处理.大量计算结果表明,该反应服从二级动力学模型,表观反应活化能为213.59kJ·mol~(-1),指前因子为5.903×10~(25)dm~3·mol~(-1)·min~(-1)计算结果的合理性及一致性,进一步证明了动态原理用于液-固相反应体系的动力学研究是简便可行的     

煤沥青改质非等温动力学研究

The non-isothermal kinetics for mesophase transformation of Baogang-I coal tar pitch (I-CTP), soft pitch consisted of I-CTP and 18% phenanthrene residue oil (PRO) or I-CTP and 30% PRO have been studied in a thermal conversion unit. Kinetic parameters were calculated by using an integral method. Results showed that the process of mesophase pitch transformation could be described in first order reaction. The activation energy of I-CTP is 175.36kJ/ mol. But adding 30% PRO, which improved the reactivity of I-CTP with activation energy is 138.07kJ/mol, is not beneficial to mesophase transformation.     

高岭石无定形化的动力学研究

Amorphous kaolinite derivatives were prepared through mixing kaolinite with HCOOK and KOH solution. Ki-netics of kaolinite being turned into amorphous derivatvies was investigated by XRD. It showed that the transfor-mation included dynamic and diffuse controlling stages. And the active energy E₁=26.8kJ·mol^-1; E₂=12.2 kJ·mol^-1. TEM and SEM images showed that particle size of the amorphous derivatives was about 50nm. And the amorphous derivatives seemed like alumnsilicate gel， accompanied by some aggregates.     

Isothermal and Non-Isothermal Kinetics When Mechanistic Information Available

In the case of a complex mechanism of two parallel independent reactions, peak maximum evolution methods and model-fitting methods give only a mean value of the kinetic parameters, while isoconversional methods are useful to describe the complexity of the mechanism. Isothermal and non-isothermal isoconversional methods can be used to elucidate the kinetics of the process. Nevertheless, isothermal isoconversional methods can be limited by restrictions on the temperature regions experimentally available because of duration times or detection limits. This revised version was published online in August 2006 with corrections to the Cover Date.     

配合物[Dy(p-MBA)3phen]2的合成，表征和非等温动力学

采用水溶液合成法,合成了新型配合物[Dy(p-MBA)3phen]2(p-MBA=对甲基苯甲酸;phen=1,10-邻菲啰啉)。 通过元素分析、红外光谱、摩尔电导和热分析(TG-DTG)等测试技术对配合物进行了表征。 研究了Dy(Ⅲ)配合物在静态空气气氛下的第一步热分解反应的非等温动力学。 通过用Popescu法和非线性等转化率积分法(NL-INT)的处理和计算,得到此步热分解反应的动力学方程为：dα/dT=(15.55×1012)/β·exp(-19825.60/T)3(1-α)2/3,平均活化能为164.83 kJ/mol,指前因子为15.55×1012 min-1。     

Differential Non-Linear Isoconversional Procedure for Evaluating the Activation Energy of Non-Isothermal Reactions

A differential isoconversional non-linear procedure for evaluating activation energy from non-isothermal data is suggested. This procedure was applied to model reactions (simulations) and to the dehydration of CaC₂O₄⋅H₂O. The results were compared with those obtained by other isoconversional methods. This revised version was published online in August 2006 with corrections to the Cover Date.     

Kinetics of non-isothermal decomposition of three IRGANOX-type antioxidants

In the present work a comparative kinetic study was performed on the thermal behavior of three antioxidants of IRGANOX-type (L101, L109 and L115) in dynamic air atmosphere under non-isothermal conditions. The TG-DTG data were obtained at heating rates of 5, 7, 10 and 15 K min⁻¹. The kinetic parameters were obtained by processing these data with strategies corresponding to Flynn-Wall-Ozava (FWO), Friedman (FR), Budrugeac-Segal (BS) and non-parametric kinetic (NPK) methods. The thermal degradation by all the three compounds take place in melted state, so that any kinetic models regarding the decomposition of solids are inapplicable. Only with the NPK method it was possible a separation between the two functions of the reaction rate. For the temperature dependence, f(T), an Arrhenius-type model was searched; for the conversion dependence, the Ŝestak-Berggren equation was suggested in order to discriminate between physical (m) and chemical (n or p) steps of a complex thermodegradation process.     

On the Validity of the Steady-State Approximation in Non-Isothermal Kinetics: Part IV. The case of constant rate thermal analysis

The paper investigates the validity of steady-state approximation for the case of constant rate thermal analysis experiments. It is shown that the approximation holds for the experiments run with a controlled rate of either the decomposition of the compound, or the production of gas.This revised version was published online in November 2005 with corrections to the Cover Date.     

Thermal Decomposition Kinetics of Triethylene Glycol Dinitrate

Introduction Triethylene glycol dinitrate (TEGDN) is a novel en-ergetic material containing two groups of NO2, which can be used as an energetic plasticizer ingredient in propellants because of its excellent proformance.1 It exhibits lower impact sensitivity, better thermostability, weaker poisonousness and volatility, and stronger effec-tiveness of plasticizing cellulose nitrate than nitroglyc-erine (NG). As a new plasticizer TEGDN has good ap-plication prospects in the near future. The…     

2，4，6-三硝基间苯二酚钡一水化合物的热分解动力学(英)

0IntroductionBarium2,4,6鄄trinitroresorecinatemonohydrate,Ba(TNR)·H2O,hasgooddetonatingpropertiesandissensitivetoflame.Itcanbeusedasinitiatingagent,igniterpowderordelaypowder.Itspreparation[1],pro鄄perties[1],crystalstructure[1]andthermalbehavior[2]haveb…