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1.
Haruyuki Makio Yasushi Tohi Junji Saito Mitsuhiko Onda Terunori Fujita 《Macromolecular rapid communications》2003,24(15):894-899
End‐group analyses of the oligo‐ and polypropylenes produced with bis(phenoxy‐imine) Zr and Hf complexes with methylaluminoxane (MAO) indicate that the polymerization is initiated by two consecutive 1,2‐insertions and is terminated by a β‐H transfer following a 2,1‐insertion. Our data indicate that chain propagation occurs with prevailing 1,2‐regiochemistry but with considerable regioerrors, and with virtually no stereoselectivity.
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Frdric Pelascini Frdric Peruch Pierre J. Lutz Marcel Wesolek Jacky Kress 《Macromolecular rapid communications》2003,24(13):768-771
Addition polymerization of norbornene was performed with several pyridine bis(imine) cobalt dichloride complexes activated with methylaluminoxane (MAO), first described for ethylene polymerization. For the first time, norbornene was also polymerized with CoCl2 associated to MAO. The influence of several reaction parameters has been investigated. Quite different behavior was observed compared with ethylene polymerization. Moreover, the copolymerization of ethylene and norbornene with these complexes was not possible but led to a mixture of both homopolymers.
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Wei Han Christian Müller Dieter Vogt Hans Niemantsverdriet Peter C. Thüne 《Macromolecular rapid communications》2006,27(4):279-283
Summary: A well‐defined flat model of a supported homogeneous polyolefin catalyst is prepared on the basis of an immobilized bis(imino)pyridyl iron complex on a super flat silica surface. The amount of supported catalyst precursor is quantified using XPS. This model catalyst remains active over extended periods, i.e., an average activity of 0.25 × 103 kg PE · (molCat · h · bar)−1 is obtained for 24 h of ethylene polymerization. The morphology of the nascent polyethylene film is investigated by SEM.
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Polymerizations of vinyl ethers are carried out with (α‐diimine)nickel(II ) catalysts in the presence of methylaluminoxane. Effects of structural variations of the ligand on the activities of catalysts and polymer microstructure are described. The catalysts prepared by changing the bulkiness of ligand substituents in the ortho aryl position result in no specific trends terms of the yield and molecular weight of polymer. Poly(vinyl ether)s are atactic regardless of the structure of the catalyst used.
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Sei‐ichi Ishii Rieko Furuyama Naoto Matsukawa Junji Saito Makoto Mitani Hidetsugu Tanaka Terunori Fujita 《Macromolecular rapid communications》2003,24(7):452-456
The catalytic properties of bis(phenoxy‐imine) Zr and Hf complexes incorporating perfluorophenyl groups with methylaluminoxane were investigated. The fluorinated complexes produced far higher‐molecular‐weight polyethylenes and ethylene/propylene copolymers with increased activities compared with the non‐fluorinated congeners. Moreover, the fluorinated complexes displayed a higher incorporation ability for propylene.
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Harsha D. Magurudeniya Prakash Sista Jacob K. Westbrook Taryn E. Ourso Khuong Nguyen Marie C. Maher Mussie G. Alemseghed Michael C. Biewer Mihaela C. Stefan 《Macromolecular rapid communications》2011,32(21):1748-1752
A nickel α‐diimine catalyst was used for Grignard metathesis (GRIM) polymerization of 2,5‐dibromo 3‐hexylthiophene and 2‐bromo‐5‐iodo‐3‐hexylthiophene monomers. GRIM polymerization of 2‐bromo‐5‐iodo‐3‐hexylthiophene generated regioregular polymers with molecular weights ranging from 3 000 to 12 000 g · mol−1. The nickel α‐diimine catalyst was also successfully used for the GRIM polymerization of a bulky benzodithiophene monomer.
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Summary: A water‐soluble gold nanoparticle aggregate 2 was prepared by chloroauric acid and a polypseudorotaxane 1 of mono‐6‐thio‐β‐cyclodextrin with poly(propylene glycol) bis(2‐aminopropyl ether) ( ≈ 2 000) in the presence of sodium borohydride in N,N‐dimethylformamide (DMF) solution. The investigative results indicated that the gold nanoparticle aggregate 2 might act as an efficient DNA‐cleavage reagent.
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Seok‐Ho Hwang Pingshan Wang Charles N. Moorefield Jae‐Chang Jung Jeong‐Yeol Kim Sang‐Won Lee George R. Newkome 《Macromolecular rapid communications》2006,27(21):1809-1813
Summary: An O‐hexyl‐3,5‐bis(terpyridine)phenol ligand has been synthesized and transformed into a hexagonal Zn(II)‐metallomacrocycle by a facile self‐assembly procedure capitalizing on terpyridine‐Zn(II)‐terpyridine connectivity. The structural composition was confirmed by NMR and mass spectral techniques; photo‐ and electroluminescence properties were also investigated. The OLED device shows green electroluminescent emission at 515 nm with a maximum luminance of 39 cd · m−2 and maximum efficiency of 0.16 cd · A−1.
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Emilio Scamporrino Sebastiano Bazzano Daniele Vitalini Placido Mineo 《Macromolecular rapid communications》2003,24(3):236-241
The preparation of a bisphenol‐A carbonate copolymer, containing Cu‐diimine units with nonlinear optical (NLO) properties, and its MALDI‐TOF mass spectrometric characterization are reported. Contrary to the usual synthetic method, NLO groups were inserted directly into a commercial polycarbonate by prolonged heating at 250 °C. This innovative procedure allows to obtain a Cu/diimine‐containing polymer of high molecular weight.
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Summary: The synthesis, morphology, and photophysical properties of PF‐b‐PAA with different coil lengths in dilute solutions of dichloromethane/methanol are reported. A tape‐like lamellar morphology is observed at a short coil length of PF‐b‐PAA. As the coil length increases, a large compound micelle, sphere, or vesicle is observed with different methanol contents because of the enhancement of the PAA swelling with methanol and the interfacial tension between the PF core and the PAA corona. Upon further increase of the coil length, an inverted morphology of a sphere or rod with a PF corona and PAA core is first observed but the core/corona is then reversed at a high methanol content as a result of the enhanced solubility of PAA. The morphological transformation leads to a significant variation in optical absorption or fluorescence characteristics because of the possible H‐aggregate formation.
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Faruk Yilmaz Ioan Cianga Koichi Ito Takamichi Senyo Yusuf Yagci 《Macromolecular rapid communications》2003,24(4):316-319
A novel α,ω‐heterofunctional poly(ethylene oxide) (PEO) macromonomer possessing methacryloyl and thienyl end groups was prepared by ring‐opening polymerization of ethylene oxide initiated by potassium thienylethoxide and termination of the living PEO ends with methacryloyl chloride. Incorporation of methacryloyl and thienyl groups was confirmed by free‐radical and oxidative polymerization processes, respectively, and by means of 1H NMR analysis.
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Himabindu Nandivada Hsien‐Yeh Chen Joerg Lahann 《Macromolecular rapid communications》2005,26(22):1794-1799
Summary: The vapor‐based synthesis and characterization of a reactive polymer, poly[(4‐formyl‐p‐xylylene)‐co‐(p‐xylylene)] ( 1 ), have been reported. The reactive polymer coating enables the immobilization of oligosaccharides via the chemoselective aldehyde‐hydrazide coupling reaction.
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Wing Yan Tam Chris S. K. Mak Alan Man Ching Ng Aleksandra B. Djurii Wai Kin Chan 《Macromolecular rapid communications》2009,30(8):622-626
The synthesis of poly(N‐vinylcarbazole)‐based block copolymers functionalized with rhenium diimine complexes or pendant terpyridine ligands is reported. The copolymers are synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization, and they exhibit interesting morphological properties as a result of the phase separation between different blocks. The rhenium complex polymer block may function as a photosensitizer, while the terpyridine‐containing polymer block can be used as the template for nanofabrication by selective deposition of zinc complexes.
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New amphiphilic graft copolymers that have a poly(ε‐caprolactone) (PCL) biodegradable hydrophobic backbone and poly(4‐vinylpyridine) (P4VP) or poly(2‐(N,N‐dimethylamino)ethyl methacrylate) (PDMAEMA) hydrophilic side chains have been prepared by anionic polymerization of the corresponding 4VP and DMAEMA monomers using a PCL‐based macropolycarbanion as initiator. The water solubility of these amphiphilic copolymers is improved by quaternization, which leads to fully water‐soluble cationic copolymers that give micellar aggregates in deionized water with diameters ranging from 65 to 125 nm. In addition, to improve the hydrophilicity of PCL‐g‐P4VP, grafting of poly(ethylene glycol) (PEG) segments has been carried out to give a water‐soluble double grafted PCL‐g‐(P4VP;PEG) terpolymer.
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A novel approach is employed to produce core–corona nanospheres, which introduces a stereoregular hydrophilic part to an amphiphilic block copolymer. The resultant morphology is reported using isotactic‐poly(methacrylic acid)‐block‐poly(butyl acrylate). Infrared spectroscopy revealed a supramolecular interaction, and X ray diffraction revealed the crystallization of the outer isotactic‐poly(methacrylic acid) part. The nanostructure, which looks like a nanosized ‘grape’, was formed when nanospheres and nanofibers coexisted simultaneously and partially fused.
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Qiang Fang Biao Jiang Bing Xu Wanjun Wang Feng Yu Xiaqin Wu 《Macromolecular rapid communications》2004,25(15):1429-1432
Summary: A class of new, soluble, π‐conjugated polymers containing a fumaronitrile unit in the main chain were synthesized by the reaction between di(4‐bromophenyl)fumaronitrile and bis(2,2‐dimethylpropane‐1,3‐diyl)‐1,4‐dialkoxyphenylene‐2,5‐diborate employing palladium catalysts. All the polymers were photoluminescent and electrochemically active.