首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 421 毫秒
1.
酸性离子液体催化合成二甘醇双丙烯酸酯   总被引:2,自引:0,他引:2  
二甘醇双丙烯酸酯(Diethylene glycol diacrylate,简称DEGDA),是重要的丙烯酸多官能酯类单体之一,作为紫外光固化树脂的活性稀释剂,广泛用于光固化涂料、印刷油墨、感光树脂版、印刷线路版等领域[1].目前,合成DEGDA多用浓硫酸为催化剂,其反应底物一般可形成均相分散体系,有利于反应物间充分接触,反应速度快.缺点是浓硫酸的脱水性和强氧化性,导致反应中副反应多,设备腐蚀严重,大量"三废"的排放给环境保护造成极大的压力[2].  相似文献   

2.
原位分散紫外光固化SiO_2纳米复合材料的性质   总被引:1,自引:0,他引:1  
紫外光固化技术是以紫外光为辐射光源使体系快速固化的技术 ,具有易散热、快速固化成型、百分之百转化率、固化材料质量高等诸多优点 ,可用来制备各种功能材料 [1~ 3] .Adrian等[4] 在紫外光可固化材料中利用分散法填充各种传统填料 ,提高了固化材料的力学性能 .本文将 Si O2 纳米粒子分散在环氧丙烯酸酯齐聚体等构成的紫外光可固化溶液中 ,制得了 Si O2纳米复合材料 .试验表明 :原位分散紫外光固化合成纳米复合材料具有快速固化、容易成型、基体可选等优点 ,所得 Si O2 纳米复合材料具有良好的力学和光学性能 .试剂与仪器 :双酚 A环氧…  相似文献   

3.
紫外光固化反应按机理分为自由基固化、阳离子固化以及自由基-阳离子混杂固化.自由基-阳离子混杂固化是指在同一体系里同时通过自由基聚合和阳离子聚合而发生的固化[1].混杂聚合结合了各个聚合反应的优点,表现出很好的协同效应.杂化光引发剂被设计成既能引发自由基聚合又能引发阳离子聚合的光引发剂.据报道,目前常见的杂化光引发剂主要有碘鎓盐类和苯基膦二苯甲酮类[2].  相似文献   

4.
一.专著作者.书名[M].版本(第1版不著录).出版地:出版单位,出版年.起止页码.示例:[1]Griffiths L.Colour and Constitution of Organic Molecules[M].London:Academic Press,1976.25-32.[2]王德海,江棂.紫外光固化材料理论与应用[M].北京:科学出版社,2001.316-319.  相似文献   

5.
《影像科学与光化学》2020,(3):I0001-I0001
一.专著作者.书名[M].版本(第1版不著录).出版地:出版单位,出版年.起止页码.示例:[1]Griffiths L.Colour and Constitution of Organic Molecules[M].London:Academic Press,1976.25-32.[2]王德海,江棂.紫外光固化材料理论与应用[M].北京:科学出版社,2001.316-319.二.期刊作者.文章题名[J].  相似文献   

6.
水性紫外光固化树脂的研究进展   总被引:3,自引:0,他引:3  
综述了近年来水性紫外光固化树脂及其涂料制备的最新研究进展.详细介绍了各类水性紫外光固化树脂的结构特点、制备方法及其在涂料中的应用情况,尤其对水性紫外光固化环氧树脂、聚氨酯树脂和超支化聚合物树脂等作了重点介绍,并展望了本领域的未来发展趋势.  相似文献   

7.
羟基磷灰石和胶原是人体骨的主要成分,近年来,制备纳米羟基磷灰石/ 胶原复合材料已成为目前生物材料研究的热点之一[1-3].海藻酸钠是一种酸性的多聚糖,具有良好的生物相容性,目前已经被广泛应用于化学、生物、医药、食品等领域;海藻酸钠能与钙离子交联,可进一步获得具有良好弹性性能的网状结构[4,5].  相似文献   

8.
正一.专著作者.书名[M].版本(第1版不著录).出版地:出版单位,出版年.起止页码.示例:[1]Griffiths L.Colour and Constitution of Organic Molecules[M].London:Academic Press,1976.25-32.[2]王德海,江棂.紫外光固化材料理论与应用[M].北京:科学出版社,2001.316-319.Wang D H,Jiang L.Theory and Application of UV-curing Material[M].Beijing:Science Press,2001.316-319.  相似文献   

9.
<正>一.专著作者.书名[M].版本(第1版不著录).出版地:出版单位,出版年.起止页码.示例:[1] Griffiths L.Colour and Constitution of Organic Molecules[M].London:Academic Press,1976.25-32.[2]王德海,江棂.紫外光固化材料理论与应用[M〗.北京:科学出版社,2001.316-319.Wang D H,Jiang L.Theory and Application of UV-curing Material[M].Beijing:Science Press,2001.316-319.  相似文献   

10.
<正>一.专著作者.书名[M].版本(第1版不著录).出版地:出版单位,出版年.起止页码.示例:[1]Griffiths L.Colour and Constitution of Organic Molecules[M].London:Academic Press,1976.25-32.[2]王德海,江棂.紫外光固化材料理论与应用[M〗.北京:科学出版社,2001.316-319.Wang D H,Jiang L.Theory and Application of UV-curing Material[M].Beijing:Science Press,2001.316-319.  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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%).  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号