化学改性环氧树脂水基涂料的研究——涂膜性能

用对氨基苯甲酸改性环氧树脂 ,使其具有亲水亲油两亲性质 ,测定了改性产物和纯环氧树脂共混物的玻璃化转变温度 ,结果显示两者能够相容 ,并以改性产物及其与纯环氧树脂的混合物制备水基涂料 ,测定了涂膜的物理和化学性能。结果表明 ,涂膜性能优良 ,保持了溶剂型环氧涂料的抗冲击强度、光泽度和硬度等方面的优点 ,而附着力提高 ,同时柔韧性大为改善 ,涂膜耐水性和耐化学药品性能优良。     

化学改性环氧树脂水基涂料的研究-涂膜性能

化学改性环氧树脂水基涂料的研究-涂膜性能     

双组分水性环氧树脂涂料

简述了双组分水性环氧树脂涂料的特点及其用途，分别介绍了水性环氧树脂乳液和水性环氧固化剂的制备方法、双组分水性环氧树脂涂料的分类、混合体系的固化成膜机理和适用期的判断。最后给出了对水性环氧树脂涂料进行配方设计时应考虑的因素。     

环氧树脂体系固化反应及其复合材料介电性能

环氧树脂是一类综合性能优异的热固性高分子材料，作为胶粘剂、复合材料用树脂基体、涂料等形式广泛应用于电子电气、机械制造、化工防腐、航空航天等众多领域中，成为各工业领域中不可缺少的基础材料。本文综述了本研究室在咪唑／环氧树脂体系，稀土有机化合物、叔胺羧酸复盐／酸酐／环氧树脂体系，氰酸酯／环氧树脂体系，硼胺络合物／环氧树脂体系的固化反应机理、固化反应动力学及其固化物结构与性能关系，纤维含量、排列方向、偶联剂种类等对玻璃纤维增强环氧树脂基复合材料及其界面介电性能的影响等6个方面的研究进展。     

有机硅改性环氧树脂的新进展

热固性环氧树脂材料具有良好的物理、化学等诸多优异性能,对于金属和非金属材料的表面都具有优异的粘接强度,可用于浇注、浸渍、层压、粘接剂、涂料等,用途十分广泛。由于环氧树脂材料存在脆性大,抗冲击性差、耐热性差等缺点,科研工作者对环氧树脂进行了大量的改性研究并取得了丰硕的成果。有机硅化合物改性环氧树脂在提高其热氧稳定性、韧性以及耐烧蚀性能等方面具有独特的优势,近年来,研究人员利用功能性有机硅化合物或聚合物在环氧树脂进行改性方面,开展了反应共聚改性、作为交联剂固化改性、与环氧树脂共混/交联改性、增容改性、互穿聚合物网络(IPN)、引入阻燃剂结构改性以及微纳米复合改性等方面的研究,取得了很多新的成果。本文旨在总结上述各种有机硅改性环氧树脂研究的新进展,并预测了有机硅改性环氧树脂材料的潜在应用和发展方向。     

噁唑烷酮环氧树脂的研究进展

含噁唑烷酮结构的树脂具有优良的耐热性、电性能及物理机械性能等。将噁唑烷酮环引入环氧树脂,可提高固化物的玻璃化转变温度、粘结性、介电性和阻燃性等。本文综述了噁唑烷酮环氧树脂的一般合成方法,探讨了原料配比、反应温度、催化剂种类及用量对噁唑烷酮环氧树脂合成过程的影响,分析了固化剂与噁唑烷酮环氧树脂固化产物性能之间的联系,对噁唑烷酮环氧树脂在绝缘材料、涂料、粘合剂、印刷电路板以及高性能树脂基体等领域的应用情况进行了详细介绍,并对其发展前景予以展望。     

聚硫橡胶对环氧胶粘剂的增韧作用研究

环氧树脂以其优良的粘接性、化学稳定性、工艺性等性能,在粘接、涂料、机械、电子、国防等领域有广泛的应用[1].环氧树脂改性及工艺研究的相关报道较多[2-9].环氧树脂固化后有脆性大的缺点,在一定程度上限制了环氧树脂的应用.采用液体橡胶增韧环氧胶是改善环氧胶脆性的有效途径.本文介绍了采用聚硫橡胶增韧环氧胶的方法,并且研究了增韧后环氧胶的力学性能.     

环氧─聚氨酯阴极电泳涂料的研制

以聚酰胺改性的环氧树脂为主链，聚醚封端的异氰酸酯为交联剂，选择适当的催化剂和助溶剂，制备出了脱封温度较低，成膜时间较短，性能稳定的水溶性环氧一聚氨酯阴极电泳涂料。本文考察了反应温度，投料顺序，催化剂浓度对反应速度的影响；对影响电泳涂料性能和漆膜性能的因素进行了讨论。     

环氧树脂水基化化学改性的研究

用对氨基苯甲酸改性环氧树脂 ,使其成为具有亲水性的树脂。测定了改性树脂的溶解性 ,发现改性后树脂在有机溶剂中的溶解性能变差 ,但在碱性溶剂中溶解性增强。对改性树脂进行了红外光谱表征 ,并根据环氧基特征峰的吸收对环氧基转化率进行了定量分析。测定了改性产物的DSC曲线 ,发现随着反应物中对氨基苯甲酸比例的提高 ,改性产物的玻璃化转变温度升高。涂膜的性能测试表明 ,对氨基苯甲酸改性环氧树脂水基涂料的机械力学性能和耐化学试剂性能比溶剂型纯环氧树脂要优越。     

液晶环氧树脂复合材料的研究进展

综述了液晶环氧树脂复合材料的国内外研究进展，介绍了液晶环氧树脂复合材料的种类和各种液晶环氧树脂复合材料的性能，并简述了液晶环氧树脂复合材料研究发展方向。     

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.     

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.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.