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331.
Tadashi Narita Tokio Hagiwara Hiroshi Hamana Kazuyuki Enomoto Yasuhiko Yoshida Yuuichi Inagaki 《Macromolecular rapid communications》1998,19(9):485-491
To develop a radical polyaddition reaction of 2-benzoyloxypentafluoropropene [CF2C(CF3)-OCOC6H5] (BPFP) with tetrahydrofuran (THF), the reactions of bis(α-trifluoromethyl-β-difluorovinyl) terephthalate [CF2C(CF3)OCOC6H4COOC(CF3)CF2] (BFP) with THF and of BPFP with 1,4-dioxane were investigated as model reactions to form 1 : 1 and 1:2 addition products of BFP with THF. This evidenced that THF is monofunctional, and dioxane is bifunctional since the 1:1 and 2:1 addition products of BPFP with dioxane were formed. The polyaddition reaction of BFP with dioxane turned out to produce a white powdery substance which was found to possess a mole ratio of BFP units to dioxane units in the polymers of 1:1. The highest molecular weight obtained was M n = 9.9 × 103. 相似文献
332.
Yasuhiko Kurusu 《Macromolecular Symposia》1996,105(1):173-177
Manganese chelates were prepared and the autoxidation of isopropyl benzene (IP) was carried out. (Mn-Chelate-1) showed a long induction period, but the other complexes (Mn-Chelate-2 and −3) which contain two or more magnesium ions in each molecule had shorter induction periods. The difference comes from the conformation around the manganese ion. Mn(III) acetate prepared from the oxidation of manganese (II) acetate with potassium permanganate in acetic acid was discussed. 相似文献
333.
Yoji Ikeda Yasuhiko Yoshida Kenji Ishihara Hiroshi Hamana Tadashi Narita Tokio Hagiwara 《Macromolecular rapid communications》1996,17(10):713-721
Novel copolymers consisting of 3,3,3-trifluoro-1,2-epoxypropane (TFEP) and N-phenylmaleimide (PMI) units were prepared by the copolymerization of TFEP with PMI initiated with an organozinc compound. Using [Zn(OCH3)2 · (C2H5ZnOCH3)4] as an initiator, the copolymer chains consisted mainly of TFEP-TFEP sequences. The TFEP-PMI sequence content in the copolymer chains was small. On the other hand, using (C2H5ZnOCH3)4 as an initiator, only low molecular weight copolymers were formed. Those copolymers were suggested to have block structure, poly(TFEP)-block-poly(PMI), by the 19F NMR analysis. The copolymers showed higher thermostability than poly-(TFEP). 相似文献
334.
Yasuhiko Kurusu 《Macromolecular Symposia》1992,59(1):313-318
Silica gel was modified with (N,N-dimethyl-3- aminopropyl)trimethoxysilane and the functionalized silica catalysts thus prepared complexed with iron and copper to produce FS-1{Fe},FS-1{Cu}. 11.2% of methylcyclohexane was oxidized in the presence of oxygen with FS-1(Fe) at 60°C. 2-Hydroxymethylcyclohexane was obtained in 59% yield. The structural differences between FS-1 (Fe)and FS-1 {Cu} are discussed. 相似文献
335.
A Bis(phenoxy‐imine)Zr Complex for Ultrahigh‐Molecular‐Weight Amorphous Ethylene/Propylene Copolymer
Seiichi Ishii Junji Saito Sadahiko Matsuura Yasuhiko Suzuki Rieko Furuyama Makoto Mitani Takashi Nakano Norio Kashiwa Terunori Fujita 《Macromolecular rapid communications》2002,23(12):693-697
A new bis(phenoxy‐imine)Zr complex has been developed. This complex in conjunction with iBu3Al/Ph3CB(C6F5)4 at 70°C produces ultrahigh‐molecular‐weight amorphous ethylene/propylene copolymer with a weight‐average molecular weight of 10 200 000 g/mol versus polystyrene standards, which represents the highest molecular weight known for linear, synthetic copolymers to date. 相似文献
336.
Yasuhiko KURUSU 《高等学校化学学报》1998,19(Z1):40
The oxidation of organic substrates leads to the production of many functionalised molecules which are of great commercial and synthetic importance. The conventional mode of oxidation which involves stoichiometric ammount of Cr or Mn salts has been staked out because of the environmental hazadrous process. The transition to cleaner, safer, and more efficient plants is a new paradigm in the synthetic organic chemistry. Nowadays, hydrogen peroxide and oxygen as oxidizing agents were extreamely valuable and attractive. It is increasingly recognized, when polymers are used as supports for catalysts or organic reagents, the reactivity and selectivity of the supported catalysts or reagents may be seriously changed by so-called "polymer effects". As metal catalyzed oxidation of organic substrates with oxygen, we arc planing the incorporation of transition metals into polymer. In oxidaton organic compound has little resistant, so syntheses of organic-inorganic hybrid polymer from silica gel and montmorillonite by the modification with silane coupling reagents and the complexation of transition metal ions into hybrid polymer obtained above were investigated. 相似文献
337.
Yasuhiko Suzuki Yoshihisa Inoue Hidetsugu Tanaka Terunori Fujita 《Macromolecular rapid communications》2004,25(3):493-497
Summary: Bis(phenoxy–ether) Ti complexes were investigated as ethylene polymerization catalysts. The complexes, combined with iBu3Al/Ph3CB(C6F5)4 or methylaluminoxane (MAO) cocatalysts, can be highly active single‐site catalysts, which display activities ( turnover frequency, max. 2 065 min−1) comparable with that of a highly active bis(phenoxy–imine) Ti complex/MAO system, and provide very high molecular weight polyethylenes ( 2 040 000–5 420 000) at 25 °C under atmospheric pressure.
338.
Masayori Fujioka Hideyuki Okada Yukihiko Kusaka Satoko Nishiyama Hiromichi Noguchi Shigeru Ishii Yasuhiko Yoshida 《Macromolecular rapid communications》2004,25(20):1776-1780
Summary: The title polymers, in which both the stem and the graft are biodegradable, have been synthesized for the first time in a one‐pot, lipase‐catalyzed, graft‐polymerization reaction (in bulk, at 70 °C) of β‐butyrolactone (β‐BL) and ε‐caprolactone (ε‐CL) onto chitin and chitosan. The reactivity order of the lactones was found to be ε‐CL > β‐BL ≫ γ‐BL (no reaction). All the graft polymers prepared are insoluble in common organic solvents.
339.
340.
Formation of a Nonlinear Optical Host–Guest Hybrid Material by Tight Confinement of LDS 722 into Aluminophosphate 1D Nanochannels 下载免费PDF全文
Rebeca Sola‐Llano Dr. Virginia Martínez‐Martínez Dr. Yasuhiko Fujita Dr. Luis Gómez‐Hortigüela Dr. Almudena Alfayate Prof. Hiroshi Uji‐i Prof. Eduard Fron Prof. Joaquín Pérez‐Pariente Prof. Iñigo López‐Arbeloa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15700-15711
In this work, hemicyanine dye LDS 722 is encapsulated into the 1D elliptical nanochannels of MgAPO‐11 aluminophosphate by a crystallization inclusion method. The synthesis of the hybrid material has been optimized through a systematic variation of the crystallization conditions in order to obtain pure and large crystals (around 20 μm×30 μm) suitable for optical applications. The tight fitting between the molecular size of the guest dye and the pore dimensions of the host has favored a rigid planar conformation of the dye, restricting its inherent flexibility, which is confirmed by molecular simulations. Consequently, the encapsulation of LDS 722 into MgAPO‐11 has led to an astonishing enhancement of the fluorescence with respect to the dye into MgAPO‐5, with slightly larger cylindrical channels, and with respect to the dye in solution. Moreover, the perfect alignment of LDS 722 (dye with intrinsic nonlinear‐optical properties) along the channels of MgAPO‐11 has revealed attractive second‐order nonlinear properties, such as second harmonic generation, proven through microscopy measurements in single crystals. 相似文献