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101.
Naphthalic anhydride derivatives: Structural effects on their initiating abilities in radical and/or cationic photopolymerizations under visible light 下载免费PDF全文
Pu Xiao Frédéric Dumur Jing Zhang Bernadette Graff Fabrice Morlet‐Savary Jean Pierre Fouassier Didier Gigmes Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(24):2860-2866
Only one naphthalic anhydride derivative has been reported as light sensitive photoinitiator, this prompted us to further explore the possibility to prepare a new family of photoinitiators based on this scaffold. Therefore, eight naphthalic Naphthalic anhydride derivatives (ANH1‐ANH8) have been prepared and combined with an iodonium salt (and optionally N‐vinylcarbazole) or an amine (and optionally 2,4,6‐tris(trichloromethyl)‐1,3,5‐triazine) to initiate the cationic polymerization of epoxides and the free radical polymerization of acrylates under different irradiation sources, that is, very soft halogen lamp (~ 12 mW cm?2), laser diode at 405 nm (~1.5 mW cm?2) or blue LED centered at 455 nm (80 mW cm?2). The ANH6 based photoinitiating systems are particularly efficient for the cationic and the radical photopolymerizations, and even better than that of the well‐known camphorquinone based systems. The photochemical mechanisms associated with the chemical structure/photopolymerization efficiency relationships are studied by steady state photolysis, fluorescence, cyclic voltammetry, laser flash photolysis, and electron spin resonance spin‐trapping techniques. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2860–2866 相似文献
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Back Cover: Porous Mn2O3: A Low‐Cost Electrocatalyst for Oxygen Reduction Reaction in Alkaline Media with Comparable Activity to Pt/C (Chem. Eur. J. 29/2016) 下载免费PDF全文
Wenhai Wang Jing Geng Long Kuai Min Li Prof. Dr. Baoyou Geng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10256-10256
106.
Jing Qu Xinran Luo Zhonggang Wang 《Journal of polymer science. Part A, Polymer chemistry》2016,54(13):1969-1977
Tetrakis(4‐(1‐bromoethyl)phenyl)silane is synthesized and utilized to initiate the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) to generate bromo‐terminated four‐armed PMMA macroinitiators, which further initiate the ATRP of methylacryloyloxyl‐2‐hydroxypropyl perfluorooctanoate (FGOA) to create fluorinated star‐shaped block copolymers PMMA‐b‐poly(FGOA)s with fluorine content ranging from 0 to 31.7 wt %. The polymerizations are well controlled with the polydispersity indices <1.30. The polymers readily dissolve in common organic solvents and show good film‐formation. Compared with the nonfluorinated sample, the fluorinated films exhibit significantly increased water contact angles owing to the enrichment of fluorine on the surface. The enhanced hydrophobicity is advantageous for the optical stability when the devices work under a moist environment. Moreover, the films possess high thermo‐optic coefficients, tunable refractive indices, and extremely low birefringence coefficients because of the presence of bulky and rigid tetraphenylsilane core and star‐shaped topological structure, showing potential application in optical waveguide devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1969–1977 相似文献
107.
Tuning of Supramolecular Architectures of l‐Valine‐Containing Dicyanoplatinum(II) 2,2′‐Bipyridine Complexes by Metal–Metal, π–π Stacking,and Hydrogen‐Bonding Interactions 下载免费PDF全文
Heidi Li‐Ki Fu Dr. Charlotte Po Dr. Hexiang He Dr. Sammual Yu‐Lut Leung Prof. Kam Sing Wong Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11826-11836
A series of newly synthesized dicyanoplatinum(II) 2,2′‐bipyridine complexes exhibits self‐assembly properties in solution after the incorporation of the l ‐valine amino units appended with various hydrophobic motifs. These l ‐valine‐derived substituents were found to have critical control over the aggregation behaviors of the complexes in the solution state. On one hand, one of the complexes was found to exhibit interesting circularly polarized luminescence (CPL) signals at low temperature due to the formation of chiral spherical aggregates in the temperature‐dependent studies. On the other hand, systematic transformation from less uniform aggregates to well‐defined fibrous and rod‐like structures via Pt???Pt and π–π stacking interactions has also been observed in the mixed‐solvent studies. These changes were monitored by UV/Vis absorption, emission, circular dichroism (CD), and CPL spectroscopies, and morphologies were studied by electron microscopy. 相似文献
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Structure/reactivity/photoinitiation ability relationships in novel benzo pyrazolo (or imidazo) isoquinolinone derivatives upon visible light LEDs 下载免费PDF全文
Pu Xiao Frédéric Dumur Jing Zhang Mariem Bouzrati‐Zerelli Bernadette Graff Didier Gigmes Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(15):1806-1815
Isoquinolinone derivatives bearing amino‐ or nitro‐ substituent (IQNs) have been synthesized as photoinitiators and combined with various additives (i.e., iodonium salt, N‐vinylcarbazole, amine or 2,4,6‐tris(trichloromethyl)?1,3,5‐triazine) to initiate ring‐opening cationic polymerizations (CP) or free radical polymerizations under exposure to visible LEDs (e.g., LEDs at 405 nm or 455 nm, or cold white LED) or a halogen lamp. Compared to the well‐known camphorquinone‐based systems, the novel IQNs‐based combinations employed here demonstrate higher efficiencies for the CP of epoxides. The photochemically generated reactive species (i.e., cations and radicals) from the IQNs‐based systems have been investigated by steady state photolysis, cyclic voltammetry, fluorescence, laser flash photolysis, and electron spin resonance spin trapping techniques. The structure/reactivity/photoinitiating ability relationships of IQNs‐based combinations are also discussed; the crucial role of the excited state lifetimes of the photoinitiators to ensure efficient quenching by additives is clearly underlined. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1806–1815 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - A new high-performance thin-layer chromatographic (HPTLC) method has been developed for the simultaneous estimation of... 相似文献