The Experts below are selected from a list of 75 Experts worldwide ranked by ideXlab platform
Jianzhong Shao - One of the best experts on this subject based on the ideXlab platform.
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efficient visible photoinitiator containing linked dye coinitiator and iodonium Salt for free radical polymerization
Progress in Organic Coatings, 2015Co-Authors: Yi Huang, Jianzhong ShaoAbstract:Abstract Dye-linked initiators consisting of erythrosine B as a chromophore and ethyl 4-dimethylaminobenzoate as an electron donor linked by a different number of methylene units were prepared to achieve efficient photoinitiators of free radical polymerization in a visible-light region. The relative photoinitiating efficiencies of novel photoinitiators in photopolymerization of acrylates were evaluated. The results showed that the photoinitiating system composed of the dye-linked dyad with short methylene unit chain and Diphenyliodonium Salt exhibited a remarkable increase in the photoinitiation ability compared to unlinked three-component system. The enhancement mechanism aroused by the onium Salt was investigated. These results showed that the excellent initiating efficiency of this system could be attributed to the favorable intramolecular photoinduced electron transfer and the close distance between reaction components caused by electrostatic interactions. This result demonstrated the importance and potential of the linked photoinitiator in the design of new efficient photoinitiators.
Yi Huang - One of the best experts on this subject based on the ideXlab platform.
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efficient visible photoinitiator containing linked dye coinitiator and iodonium Salt for free radical polymerization
Progress in Organic Coatings, 2015Co-Authors: Yi Huang, Jianzhong ShaoAbstract:Abstract Dye-linked initiators consisting of erythrosine B as a chromophore and ethyl 4-dimethylaminobenzoate as an electron donor linked by a different number of methylene units were prepared to achieve efficient photoinitiators of free radical polymerization in a visible-light region. The relative photoinitiating efficiencies of novel photoinitiators in photopolymerization of acrylates were evaluated. The results showed that the photoinitiating system composed of the dye-linked dyad with short methylene unit chain and Diphenyliodonium Salt exhibited a remarkable increase in the photoinitiation ability compared to unlinked three-component system. The enhancement mechanism aroused by the onium Salt was investigated. These results showed that the excellent initiating efficiency of this system could be attributed to the favorable intramolecular photoinduced electron transfer and the close distance between reaction components caused by electrostatic interactions. This result demonstrated the importance and potential of the linked photoinitiator in the design of new efficient photoinitiators.
Takeshi Endo - One of the best experts on this subject based on the ideXlab platform.
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enhanced degradation of cellulose acetate film containing Diphenyliodonium Salt benzophenone
Cellulose, 2007Co-Authors: Kiyoshi Hosono, Akihiko Kanazawa, Hideharu Mori, Takeshi EndoAbstract:Cellulose acetate (degree of substitution 2.45) films containing Diphenyliodonium Salt and benzophenone were prepared and their degradative behavior was examined under simulated solar exposure. Acetic acid generation from the films under irradiation was greater in the co-presence of Diphenyliodonium Salt and benzophenone than in the sole presence of Diphenyliodonium Salt. Photosensitization and free-radical oxidization, which are followed by Bronsted acid generation, were postulated as the mechanism for the observed increase of deacetylation. The patterns of decreased molecular weight were different between the films with the Diphenyliodonium Salt and those with benzophenone; while the films with the Diphenyliodonium Salt kept a relatively constant molecular-weight distribution, the polydispersity increased in the films with benzophenone during the degradation. Since the synthesized characteristics of those two different patterns of change in molecular-weight distribution were observed in the co-presence of the Diphenyliodonium Salt and benzophenone, each additive appeared to act independently to lead to main-chain cleavage of cellulose acetate. Therefore, decrease in the molecular weight of cellulose acetate by Diphenyliodonium Salt did not seem to be enhanced in the co-presence with benzophenone.
Kazutoshi Suzuki - One of the best experts on this subject based on the ideXlab platform.
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a practical route for synthesizing a pet ligand containing 18f fluorobenzene using reaction of Diphenyliodonium Salt with 18f f
Tetrahedron Letters, 2007Co-Authors: Mingrong Zhang, Katsushi Kumata, Kazutoshi SuzukiAbstract:Abstract The aim of this study was to develop a practical route for preparing a fluorine-18 ([18F]) labelled ligand ([18F]1) containing [18F]fluorobenzene ring by employing the reaction of Diphenyliodonium Salt with [18F]F−. Diphenyliodonium tosylate (2) was synthesized from tributylphenylstannyl compound (6) with [hydroxy(tosyloxy)iodo]benzene (7). Using this method, [18F]DAA1106 ([18F]3a), a positron emission tomography ligand for imaging peripheral-type benzodiazepine receptor, was prepared.
Kunihiro Ichimura - One of the best experts on this subject based on the ideXlab platform.
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triplet state electron transfer pathway for tetrabenzoporphyrin Diphenyliodonium Salt photoinitiator system
Journal of Photochemistry and Photobiology A-chemistry, 1992Co-Authors: Madoka Yasuike, Motoyuki Shima, Kenichi Koseki, Tsuguo Yamaoka, Masako Sakuragi, Kunihiro IchimuraAbstract:Abstract A triplet state electron transfer mechanism for the photoreaction between meso -diphenyl-tetrabenzoporphyrin (P 2 TBP) metallo complexes, e.g. magnesium (1a, MgP 2 TBP), zinc (1b, ZnP 2 TBP) and cadmium (1c, CdP 2 TBP), and Diphenyliodonium (DPI) Salt was confirmed by the detection of the cation radicals of P 2 TBP using nanosecond laser flash photolysis equipment, as expected from the estimation of the free energy changes (ΔG T ). Rate constants ( T k q ) of the triplet state quenching of metallo P 2 TBP complexes by DPI, determined from the slopes of Stern-Volmer plots, approximately obeyed a diffusion-controlled limit in accordance with fully exothermic ΔG T values. Since the fluorescence of the magnesium and zinc complexes was quenched by DPI at high concentrations (above 10 −3 M), as previously reported, both excited states were deactivated by the onium Salt, depending on its concentration. However, it was presumed that a triplet state electron transfer pathway was preferred for the cadmium complex because of its short fluorescence lifetime.
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positive working resists sensitive to visible light i poly tert butyl and 2 phenylpropyl 2 methacrylates sensitized with Diphenyliodonium Salt p aminobenzylidene dye system
Polymers for Advanced Technologies, 1992Co-Authors: Yasushi Ohe, Kunihiro IchimuraAbstract:Visible-light-sensitive positive type resists have been developed. The chemistry to form images is based on the cleavage of side chain ester bonds of poly(methacrylates) catalyzed by an acid which is generated on sensitized photodecomposition of a Diphenyliodonium (DPI) Salt. Homopolymers and copolymers of tert-butyl methacrylate (BMA) and 2-phenylpropyl-2 methacrylate (PPMA) were used as acid labile polymers. Exposure of thin films of the poly(methacrylates) containing DPI Salt and p-dimethylaminobenzylidene derivatives to an Ar laser beam emitting 488 nm light and subsequent heat treatment resulted in solubility alteration of the polymers, which became soluble in a protic solvent system. Considerable reduction of film thickness was observed after heating an image-wise exposed thin film of PPMA polymers. The minimum exposure energies of 488 nm light for the positive image formation were 60 mJ/cm2 and 40 mJ/cm2 for BMA and PPMA homopolymers, respectively.