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The effect of initiators and oxidants on the morphology of poly [(±)‐2‐(sec‐butyl) aniline] a chiral bulky substituted polyaniline derivative 下载免费PDF全文
The nano and micro sphere synthesis of chiral bulky substituted polyaniline from monomer (±)‐2‐sec‐butylaniline in bulk and template‐free method (rapid mixing) was done successfully using ammonium peroxydisulfate (APS) and FeCl3·6H2O as oxidants. The effect of initiators such as p‐phenylendiamine and 1,4‐benzenediamine, temperature and concentration of monomer on morphology is demonstrated by scanning electron microscopy (SEM) images. The nano and micro sphere morphology was obtained using initiators. Smallest particles were achieved when 1,4‐benzenediamine was used as initiator in the presence of FeCl3·6H2O as oxidant. By increasing the concentration of monomer more uniform spheres were obtained. Characterization was made via FT‐IR, UV–Vis, 1H and 13C‐NMR spectroscopy. Elemental analysis and electrical conductivity of products are also presented. All analysis data are in good agreement with nigraniline oxidation state of polyaniline. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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New nickel(II) diimine complexes bearing phenyl and sec‐phenethyl groups: synthesis,characterization and ethylene polymerization behaviour 下载免费PDF全文
Fuzhou Wang Jianchao Yuan Qingshan Li Ryo Tanaka Yuushou Nakayama Takeshi Shiono 《应用有机金属化学》2014,28(7):477-483
A series of nickel(II) catalysts containing phenyl and chiral sec‐phenethyl groups, {[(4‐R1‐2‐R2C6H2N?C)2Nap]NiBr2} (Nap: 1,8‐naphthdiyl, R1 = Me, R2 = Ph ( 3a ); R1 = Me, R2 = sec‐phenethyl ( 3b ); R1 = Cl, R2 = sec‐phenethyl ( 3c ); R1 = Me, R2 = Me ( 3d ) were synthesized and characterized. All organic compounds were fully characterized by FT‐IR and NMR spectroscopy and elemental analysis. The single crystal for X‐ray crystallography was isolated from 3a in CH2Cl2/n‐hexane under air; the crystal structure showed a binuclear complex 3a ′, in which each nickel atom was six‐coordinate. The two nickel atoms together with two bromine atoms form a planar four‐membered ring, with a bromine and H2O axial ligands. These complexes, activated by diethylaluminum chloride and chiral nickel pre‐catalysts rac‐ 3c , exhibited good activities (up to 2.85 × 106 g PE (mol Ni h bar)?1) for ethylene polymerization, and produced polyethylene products with a high degree of branching (up to 117 branched per 1000 carbons) at high temperature. The type and amount of branches of the polyethylenes obtained were determined by 1H and 13C NMR spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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A. Sultan Nasar V. Shrinivas T. Shanmugam A. Raghavan 《Journal of polymer science. Part A, Polymer chemistry》2004,42(16):4047-4055
Methyl anacardate and secondary butyl anacardate were prepared from anacardic acid and corresponding alcohols and were used, in addition to cardanol, as blocking agents for 2,4‐toluene diisocyanate (TDI). Blocked diisocyanate adducts were characterized via nitrogen estimation, Fourier transform infrared spectroscopy, and proton nuclear magnetic resonance spectroscopy. The deblocking temperatures of the adducts were determined using an FTIR spectrophotometer in conjunction with the carbon dioxide evolution method. The gel times of hydroxyl‐terminated polybutadiene–TDI adducts also were determined. Deblocking temperature and gel time analyses revealed that cardanol‐blocked 2,4‐TDI deblocks at a lower temperature and at a higher rate compared with anacardate‐blocked adducts. In addition, it was found that the electron‐withdrawing ester group reduces the deblocking temperature of the adduct only when it is in solvated form. All adducts were waxy solids that were found to be soluble in polyether polyol, polyester polyol, and polyhydrocarbon polyols. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4047–4055, 2004 相似文献
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Hafid Sayah 《Comptes Rendus Mecanique》2004,332(2):161-168
The differential inclusion describing the quasi-static motion of a supple, homogeneous and inextensible string on a horizontal plane with dry friction (Coulomb's law) is a one dimensional evolution model of a continuous medium, with non-linear geometry, obeying a “plastic-rigid” law. With a view to numerical simulation, we treat the discrete case: the string is assimilated to a chain constituted by rigid rods perfectly articulated around ball-joints. We give variational formulation of the problem and prove existence and uniqueness of solutions. We construct an algorithm that describes the instantaneous solutions when the initial configuration of the string is given. Then, some examples are treated. To cite this article: H. Sayah, C. R. Mecanique 332 (2004). 相似文献
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复式断面明渠中水平热水浮力射流近区稀释特性研究 总被引:1,自引:0,他引:1
采用考虑浮力效应的RNG k-ε双方程模型,结合混合有限分析法对复式断面明渠流中水平圆孔热水浮力射流进行了数值模拟,对其近区稀释特性及二次流结构进行数值分析.同时,采用三维ADV测速仪及温度测量仪对其近区典型断面的:1) 横断面主流速等值线分布;2) 二次流;3) 横断面温度等值线分布进行了试验测量.数值模拟结果与试验资料的对比表明,考虑浮力效应的RNG k-ε模型能够较好模拟射流在环境来流、浮力效应、复式断面二次流等因素作用下,所表现出的分叉现象、附壁效应(Conada效应)和边滩二次流现象. 相似文献
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Alp H. Alidedeoglu Sandipan Dutta Rahul Misra James W. Rawlins Sarah E. Morgan 《Journal of polymer science. Part A, Polymer chemistry》2007,45(15):3191-3203
The incorporation of allylic monomers into highly reactive vinyl polymerizations provides a means to control molecular weight, conversion, and Trommsdorff effect to produce copolymers with desirable performance characteristics. The copolymerization behavior of styrene with sec‐butenyl acetate, whose copolymerization properties have not been reported, is investigated. Copolymers were produced via semicontinuous emulsion polymerization and characterized via NMR, gel permeation chromatography, differential scanning calorimetry, dynamic light scattering, and atomic force microscopy. A high degree of chain termination due to allylic hydrogen abstraction was observed, as expected, with resultant decreases in molecular weight and in monomer conversion. However, high conversions were achieved, and it was possible to incorporate high percentages of the allylic acetate comonomer into the polymer chain. Copolymer thermal properties are reported. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3191–3203, 2007 相似文献
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Chiral nickel(II) and palladium(II) catalysts bearing strong electron‐withdrawing fluorine groups: synthesis,characterization and their application in catalytic polymerization for ethylene and styrene 下载免费PDF全文
Jianchao Yuan Jie Zhao Fengying Song Weibing Xu Yanqiong Mu Jingjing Chen Zhenghua Zhang 《应用有机金属化学》2014,28(7):484-494
A series of new chiral and achiral nickel(II) and palladium(II) complexes, {bis[N,N′‐(2,6‐diethyl‐4‐naphthylphenyl)imino]‐1,2‐dimethylethane}dibromonickel 3a , {bis[N,N′‐(4‐fluoro‐2‐methyl‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel rac‐(RS)‐ 3b , {bis[N,N′‐(4‐fluoro‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel rac‐(RR/SS)‐ 3c and {bis[N,N′‐(4‐fluoro‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dichloropalladium rac‐(RR/SS)‐ 3d were successfully synthesized and characterized. The molecular structures of representative ligand rac‐(RS)‐ 2b , nickel complex 3a , rac‐(RR/SS)‐ 3c and palladium complex rac‐(RR/SS)‐ 3d were determined by X‐ray crystallography. The structures of complexes 3a and rac‐(RR/SS)‐ 3c have pseudo‐tetrahedral geometry about the nickel center, showing C2 molecular symmetry. However, the structure of palladium complex rac‐(RR/SS)‐ 3d has pseudo‐square planar geometry about the palladium center, showing C2 molecular symmetry. Complex 3e {bis[N,N′‐(2,6‐dimethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel was also synthesized for comparison. Nickel complex rac‐(RS)‐ 3b bearing strong electron‐withdrawing fluorine group in the para‐aryl position and a chiral sec‐phenethyl group in the ortho‐aryl position of the ligand (one methyl group in the ortho‐aryl position) displays the highest catalytic activity for ethylene and styrene polymerization, and produced highly branched polyethylene and syndiotactic‐rich polystyrene. However, palladium complex rac‐(RR/SS)‐ 3d shows low catalytic activity for ethylene and styrene polymerization due to the poor leaving group, Cl, attached to palladium and the unfavorable molecular structure. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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董彦杰 《新疆大学学报(理工版)》2001,(2)
通过 2 -羟基 - 5-仲辛基 -二苯甲酮肟 ( N510 )与 P53 8的氯仿溶液 ,从高氯酸介质中对钯协同萃取的研究 ,采用斜率法确定了萃合物的组成为 :L· Pd· A.协萃反应平衡常数为 lg K12 =3.114,协同萃取配合物生成常数为β12 =91.6.同时计算了协萃的热力学函数值 相似文献