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Novel Polymer (novel + polymer)
Selected AbstractsRarely Decorated Rutile Frameworks Built from Triangular Organic Spacers and Distorted Octahedral Co3 Building BlocksEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2007Feng Luo Abstract Under mild temperatures, the self-assembly of CoCl2 and H3BTC in a solution of dmso generates a guest-free metal,organic polymer, namely Co3(BTC)2(,1 -dmso)2(,2 -dmso)2(1: dmso = dimethylsulfoxide, H3BTC = 1,3,5-benzenetricarboxylic acid). In 1, the CoII ions show the six-coordinate octahedral geometry completed by the BTC3, ions and the dmso oxygen atoms; remarkably, the coordinated dmso ligands not only act as terminal ligands to complete the octahedral geometry of the CoII ions, but also play an important role in bridging CoII ions together to give the Co3 secondary building units (SBUs). From a topological viewpoint, this novel polymer is classified to be the decorated (3,6)-connected rutile net with the (4.62)2(42.610.83) topology, where BTC3, ligands and Co3 SBUs are viewed to be the 3- and 6-connected nodes, respectively. In addition, the magnetic properties of 1 are explored by using a linear trinuclear cobalt mode, thusleading to g = 2.41, J = ,34.92 cm,1, TIP = 340,×,10,6 cm3,mol,1,, = ,6 K (a , parameter was included to take into account intertrinuclear interactions).(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Synthesis and characterization of a bis-(4-trifluoromethanesulfonyloxyphenyl)phenylamine monomer and its polymer for light-emitting applicationsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2007Huseyin Zengin Abstract This study focuses on the preparation, polymerization, characterization, and optical properties of a new bis-(4-trifluoromethanesulfonyloxyphenyl)phenylamine monomer. This is the first nitrogen-containing monomer having nitrogen atoms as bridges between phenyl rings, and it was synthesized in three steps. The polymerization was carried out through the Ni(0)-catalyzed homocoupling reaction of the bis-(4-trifluoromethanesulfonyloxyphenyl)phenylamine compound. The resulting polymer, polybis(paraphenyl)phenylamine, emitted an intense blue color (where , = 415 nm) upon irradiation by ultraviolet light. The photoluminescence quantum yield was found to be 36% with a long excited-state lifetime of 3.3 ns. Electrical conductivity data for an HCl-doped film of the polymer were also examined. This novel polymer is of interest as an organic emitting material for electroluminescent devices. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1860,1867, 2007 [source] The high-resolution structure of the extracellular domain of human CD69 using a novel polymerACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2009Petr Kolenko The structure of the extracellular domain of human CD69 has been determined by single-crystal X-ray diffraction. The structure refined to 1.37,Å resolution provides further details of the overall structure and the asymmetric interface between the monomers in the native dimer. The protein was crystallized using di[poly(ethylene glycol)] adipate, which also served as a cryoprotectant. This is the first report of a crystal structure determined using crystals grown with this polymer. [source] Synthesis and characterization of sulfonated poly(benzoxazole ether ketone)s by direct copolymerization as novel polymers for proton-exchange membranesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2007Jinhuan Li Abstract A new series of sulfonated poly(benzoxazole ether ketone)s (SPAEKBO-X) were prepared by the aromatic nucleophilic polycondensation of 4,4,-(hexafluoroisopropylidene)-diphenol with 2,2,-bis[2-(4-fluorophenyl)benzoxazol-6-yl]hexafluoropropane and sodium 5,5,-carbonylbis-2-fluorobenzenesulfonate in various ratios. Fourier transform infrared and 1H NMR were used to characterize the structures and sulfonic acid contents of the copolymers. The copolymers were soluble in N -methyl-2-pyrrolidinone, N,N -dimethylacetamide, and N,N -dimethylformamide and could form tough and flexible membranes. The protonated membranes were thermally stable up to 320 °C in air. The water uptake, hydrolytic and oxidative stability, and mechanical properties were evaluated. At 30,90 °C and 95% relative humidity, the proton conductivities of the membranes increased with the sulfonic acid content and temperature and almost reached that of Nafion 112. At 90,130 °C, without external humidification, the conductivities increased with the temperature and benzoxazole content and reached above 10,2 S/cm. The SPAEKBO-X membranes, especially those with high benzoxazole compositions, possessed a large amount of strongly bound water (>50%). The experimental results indicate that SPAEKBO-X copolymers are promising for proton-exchange membranes in fuel cells, and their properties might be tailored by the adjustment of the copolymer composition for low temperatures and high humidity or for high temperatures and low humidity; they are especially promising for high-temperature applications. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2273,2286, 2007 [source] Catalytic reactions of oxetanes with protonic reagents and aprotic reagents leading to novel polymersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 5 2007Hiroto Kudo Abstract This paper reports new addition reactions of oxetanes with certain protonic reagents such as carboxylic acid, phenol, and thiol, and with certain aprotic reagents such as acyl chloride, thioester, phosphonyl dichloride, silyl chloride, and chloroformate using quaternary onium salts as catalysts. The kinetic study of the addition reactions of oxetanes was also investigated. These new addition reactions were applicable to the synthesis of new polymers. These polyaddition systems could also construct both polymer main chains and reactive side chains. The alternating copolymerization of oxetanes with carboxylic anhydride was performed. Furthermore, it was found that anionic ring-opening polymerization of oxetanes containing hydroxy groups proceeded to afford the hyperbranched polymer (HBP) with an oxetanyl group and many hydroxy groups at the ends of the polymer chains. Alkali developable photofunctional HBPs were synthesized by the polyaddition of bis(oxetane)s or tris(oxetane)s, and their patterning properties were examined, too. The photo-induced cationic polymerization of the polymers with pendant oxetanyl groups and the thermal curing reactions of polyfunctional oxetanes (oxetane resins) were also examined to give the crosslinking materials quantitatively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 709,726, 2007 [source] |