TEG-99环氧树脂的合成与性能研究

以松节油为原料合成出新型TEG - 99环氧树脂 ,研究了它分别与典型胺类、聚酰胺类及酸酐类固化剂的固化反应和固化产物的性能。结果表明 ,以松节油为原料合成TEG - 99环氧树脂的过程简单、稳定 ,产物具有与双酚A型环氧树脂相似的外观、理化性能、固化特征等 ,是松节油综合利用的一个有前景的途径     

水脱型UV防护油墨的制备及性能研究

通过将环氧树脂E44、丙烯酸、2-丙烯酰胺-2-甲基丙磺酸反应,合成了一种改性环氧丙烯酸树脂。将改性的环氧丙烯酸树脂作为主体树脂,复配活性单体、引发剂、助剂、填充料等进行混合、分散、研磨,制备得到热水脱膜UV防护油墨。将该树脂与其他丙烯酸树脂进行性能对比,并进一步探究不同活性单体、膜层厚度与光固化能量对防护油墨的性能影响。实验表明,该树脂具有较好的热水脱膜性能,当采用活性单体二乙二醇二甲基丙烯酸酯,膜层厚度为30?m及固化能量为1 500 mJ/cm2时,防护油墨综合性能最佳。     

酚醛胺复合固化高渗透弹性环氧浆液

将腰果酚、三乙烯四胺和多聚甲醛(CH2O单元计算)按照摩尔比为1∶1∶1在110~120℃下通过Mannich反应制备了含长链烷基的腰果酚酚醛胺,研究了腰果酚酚醛胺与酚醛叔胺2,4,6-三(二甲胺基甲基)苯酚的酚铵复合后催化固化以糠醛丙酮为活性稀释剂的AB双组分环氧浆液的固化机理及固结体的力学性能。结果表明,酚铵盐与腰果酚酚醛胺复合物具有良好的催化糠醛与丙酮的醇醛缩合、环氧树脂的开环聚合固化。当A组分中环氧含量在30%~40%(wt)、A/B=100∶10~20、酚铵盐在B组分中占20%(wt)时,浆液具有较低的起始粘度高渗透性及较快的固化,净浆和水泥基浆液固体体强度高,韧性大,压缩应变分别高达18%、9%。     

二元羧酸半酯与环氧化合物反应动力学研究

用于印制电路板 ( PCB)的传统的热固化或光固化阻焊油墨是利用屏印的方法把图案印刷在覆铜板上 ,然后固化 .通过这种方法得到的图案不够精细 ,应用上也受到一定限制 .为此 ,近年来国际上研制出一类新型的阻焊油墨——碱液显影型阻焊油墨 [1～ 3] .它是通过曝光、显影及后固化等步骤形成精确的图案 ,可用于制备高密度的电路板 .通常 ,碱水显影型阻焊油墨由碱溶性光敏树脂 (组分 A)、环氧化合物 (组分 B)、光引发剂、热固化剂和稀释剂组成 .组分 A由二元羧酸与含有光聚合性双键的线性酚醛型环氧化合物通过半酯化反应得到 ,羧基的引入使其具…     

双酚S/双酚A环氧树脂固化物的相容性研究

采用高分子材料动态力学谱（TBA）和傅立叶变换红外光谱（FTIR）两种方法研究了双酚S／双酚A环氧树脂／芳胺固化体系的固化过程。探讨了在双酚S环氧树脂（BPSER）和双酚A环氧树脂（BPAER）以不同质量比与固化剂4，4'- 二氨基二苯甲烷（DDM）组成固化体系中，所得固化产物的相容性。结果表明，在一个很宽的BPSER／BPAER比例范围，其固化产物具有良好的相容性。     

取代脲促进环氧树脂／双氰胺固化体系反应机理

双氰胺作为环氧树脂的固化剂，由于固化产物具有优良的机械和电性能，广泛应用在汽车、航天及电子等领域中．但由于其固化温度高达180C以上，使应用范围受到很大限制．专利文献曾报道晚衍生物作为环氧树脂／双氰胺固化体系的促进剂，可以使体系的固化温度降低到130～140oC，并且在室温下仍保持一定的潜伏性［‘，’］．在以往的研究中，认为取代脉的促进作用在于其与环氧发生反应生成环状化合物2一心竣烷酮和仲胺，仲胺与环氧基进一步反应生成的叔胺可以催化环氧发生阴离子聚合［’～’］．实验表明，环氧树脂／双氰胺／取代脉体系的固化温…     

酸酐固化环氧树脂/蒙脱土复合材料的等温固化动力学

用等温差示扫描量热法(DSC)研究了酸酐固化环氧树脂/蒙脱土复合材料的等温固化过程，考察了未处理的蒙脱土(MMT)和有机蒙脱土(OMMT)对环氧树脂固化动力学的影响. 实验表明， 环氧树脂的固化过程包含自催化机理，加入蒙脱土没有改变固化反应机理. 用Kamal方程对该体系的固化过程进行拟合，得到反应级数m、n，反应速率常数k1、k2，总反应级数(m + n)在2.4～3.0之间. MMT的加入使环氧树脂体系的k1、k2有所降低，而OMMT的加入对体系的k1、k2影响较为复杂，加入蒙脱土对环氧树脂固化体系的活化能影响较小.     

氨酯键扩链改性的669稀释剂对环氧树脂力学性能影响研究

制备了氨酯键扩链改性的669稀释剂UE6M,考察了加入不同用量的UE6M对环氧树脂进行稀释后环氧树脂混合体系的粘度变化。使用氰乙基化三乙烯四胺作为固化剂对环氧树脂混合体系进行固化,研究了UE6M的用量对环氧树脂混合体系固化物性能的影响。研究结果表明,UE6M对E51环氧树脂具有较好的稀释效果,且混合体系固化产物的韧性较纯环氧树脂固化物明显增强:UE6M用量为30%和40%的混合体系粘度仅为纯E51环氧树脂粘度的6.35%和1.43%,但其固化物的拉伸强度均在60MPa以上,分别为纯E51环氧树脂固化物的87.9%和80.9%。断裂伸长率均为纯环氧树脂固化物的8倍以上,弯曲应变为纯环氧树脂固化物2倍以上,弯曲强度及弯曲模量等未出现大幅下降,UE6M稀释剂加入环氧树脂后固化产物的韧性得到明显增强。     

2－乙基－4－甲基咪唑固化环氧树脂的固化反应机理、动力学及其反应活性

本文应用ＤＳＣ和ＦＴＩＲ对２－乙基－４－甲基咪唑固化双酚Ａ二缩水甘油醚型环氧树脂体系的固化反应机理和２－乙基－４－甲基咪唑固化双酚Ａ二缩水甘油醚型、缩水甘油酯与脂环型环氧树脂体系的固化反应特征、动力学及其反应活性进行了研究．结果表明，双酚Ａ二缩水甘油醚型环氧树脂／咪唑体系的固化反应是分两步独立进行的，第一步是加成反应，第二步是催化聚合反应．缩水甘油酯与脂环型环氧树脂（ＴＤＥ－８５）／咪唑体系的固化反应过程也分两步进行，第一阶段反应主要是缩水甘油酯型环氧基进行的加成反应和催化聚合反应，第二阶段主要是脂环型环氧基进行的加成反应．各体系第一阶段的表现反应活化能均低于第二阶段活化能．当ＴＤＥ－８５型环氧树脂中引入缩水甘油醚型环氧树脂后，固化反应速率均较ＴＤＥ－８５环氧树脂单独固化时快．     

2－乙基－4－甲基咪唑固化环氧树脂的固化反应机理、动力学及其反应活性

 本文应用ＤＳＣ和ＦＴＩＲ对２－乙基－４－甲基咪唑固化双酚Ａ二缩水甘油醚型环氧树脂体系的固化反应机理和２－乙基－４－甲基咪唑固化双酚Ａ二缩水甘油醚型、缩水甘油酯与脂环型环氧树脂体系的固化反应特征、动力学及其反应活性进行了研究．结果表明，双酚Ａ二缩水甘油醚型环氧树脂／咪唑体系的固化反应是分两步独立进行的，第一步是加成反应，第二步是催化聚合反应．缩水甘油酯与脂环型环氧树脂（ＴＤＥ－８５）／咪唑体系的固化反应过程也分两步进行，第一阶段反应主要是缩水甘油酯型环氧基进行的加成反应和催化聚合反应，第二阶段主要是脂环型环氧基进行的加成反应．各体系第一阶段的表现反应活化能均低于第二阶段活化能．当ＴＤＥ－８５型环氧树脂中引入缩水甘油醚型环氧树脂后，固化反应速率均较ＴＤＥ－８５环氧树脂单独固化时快．     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.