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11.
Synthesis of methacrylate polymer bearing cyanate groups and its chemoselective reaction with amines
Kousuke Tsuchiya Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2014,52(5):699-706
A novel reactive polymer containing cyanate groups in the side chain was prepared by free radical polymerization of a cyanate‐containing monomer, 2‐(4‐cyanatophenyl)ethyl methacrylate ( 1 ). The monomer 1 and its polymer, poly[2‐(4‐cyanatophenyl)ethyl methacrylate] (PCPMA), were stable under the air for a long period. The copolymerization of 1 and methyl methacrylate provided the corresponding copolymers with various cyanate contents. The availability of the cyanate‐containing polymers as a reactive polymer was investigated. Model reaction using 4‐cyanatotoluene revealed that a cyanate group reacted with aliphatic amines, whereas no reaction occurred in the presence of water, alcohols, and aromatic amines under mild conditions. Post‐functionalization of PCPMA was demonstrated using aliphatic amines or diamines. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 699–706 相似文献
12.
The paper concerns characterization of BMO in terms of Banach function spaces. In particular, we are interested in characterizing BMO by using the variable Lebesgue norm. 相似文献
13.
The multilayer electroluminescent(EL) devices composed of vacuum-sublimed organic films are discussed with the aims of achieving high luminance and proposing an optical micro-cavity. For the former purpose, requirements for confinements of carriers and excitons within the thin emissive layer are shown by taking accounts of ionization potentials, electron affinities and excitation energies in organic thin films. Concerning the interference effect of emitted light, we show the variation in the intensity of emission and a strongly directional light from the micro-cavity. Second-order nonlinear optical(NLO) films are designed by preparing noncentrosymmetric LB multilayers composed of an pyrazine derivative with large hyperpolarizability and arachidic acid. Third-order nonlinear optical(NLO) films are proposed by using polyarylenevinylene films. In order to fabricate excellent third-order nonlinear optical(NLO) films, highly oriented polyarylenevinylene films are prepared by using a LB technique. 相似文献
14.
15.
Mayumi Tsutsui Tokuhiro Watanabe Akihiro Ohta Kayoko Takizawa 《Journal of heterocyclic chemistry》1980,17(4):809-812
1 H-Nmr spectra of cis and trans isomers of 2,3-, 2,5-, and 2,6-dimethylpiperazines were taken at various temperatures. The spectra of geometrical isomers bearing the ae or ea dimethyl groups showed broadening at lower temperatures. It was clarified that the measurement of the spectra at lower temperatures is useful for the discrimination of the geometrical isomers of dimethylpiperazines. 相似文献
16.
Water content distribution in a polymer electrolyte membrane for advanced fuel cell system with liquid water supply 总被引:2,自引:0,他引:2
To better understand the operation of a new fuel cell design, we used magnetic resonance imaging (MRI) to measure the water content distribution in a polymer electrolyte membrane under fuel cell operation with and without a supply of liquid water. The supply of liquid water to the membrane improved the cell performance by increasing the water content in the membrane and thus reducing the electrical resistance of the membrane. The study also showed that MRI is a promising method to investigate the distribution of water in the membrane of a fuel cell under operating conditions. 相似文献
17.
We study the multiple existence of positive solutions for the following strongly coupled elliptic system:
18.
Uchiyama H Baron AQ Tsutsui S Tanaka Y Hu WZ Yamamoto A Tajima S Endoh Y 《Physical review letters》2004,92(19):197005
Phonons in nearly optimally doped HgBa(2)CuO(4+delta) were studied by inelastic x-ray scattering. The dispersion of the low-energy modes is well described by a shell model, while the Cu-O bond stretching mode at high energy shows strong softening towards the zone boundary, which deviates strongly from the model. This seems to be common in the hole-doped high-T(c) superconducting cuprates, and, based on this work, not related to a lattice distortion specific to each material. 相似文献
19.
X-ray crystallographic analysis revealed that novel silamacrocyclic compounds, 2,8,14,20-tetrasilacalix[4]quinone and 2,8,14,20-tetrasilacalix[4]hydroquinone octamethyl ether, adopted 1,3-alternate structures in the solid state. 相似文献
20.
Kenji Wada Kousuke Yano Teruyuki Kondo Take-aki Mitsudo 《Catalysis Surveys from Japan》2001,4(2):175-176