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The hybrid polymer was synthesized by a radical polymerization of a B(12) derivative and a Ru complex having styrene moieties in each peripheral position, and the hybrid polymer showed photocatalytic activity for molecular transformation with visible light irradiation., (This journal is © The Royal Society of Chemistry 2011)

A new hybrid catalyst composed of a vitamin B(12) derivative and a hyperbranched polymer (HBP) was synthesized and characterized by UV-vis and ESR spectroscopy as well as AFM. The B(12)-HBP showed good properties as a homogenous catalyst. The covalently-immobilized B(12) moieties were efficiently solvated and the cobalt centers were accessible for pyridine guests. The B(12)-HBP showed high reactivity to 2-phenethylbromide and increased selectivity for reductive dimerization in the presence of TiO(2) with UV light irradiation.

High water-soluble hyperbranched poly(styrene) (HPS) polymers carrying stable 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radicals, HPS-N-TEMPO, HPS-Im-TEMPO, and HPS-Im-(TEMPO)(2), were prepared in ca. 60% introducing yield. HPS-N-TEMPO and HPS-Im-TEMPO were determined to be nearly spherical shapes of the diameter of 2.4 +/- 0.6 and 2.2 +/- 0.6 nm, respectively, by transmission electron microscope (TEM) images. The values of water-proton relaxivity, r(1), at 25 MHz, 0.59 T, and 25 degrees C were 6.0, 5.2, and 14 mM(-1) sec(-1) for HPS-N-TEMPO, HPS-Im-TEMPO, and HPS-Im-(TEMPO)(2), respectively. The spin-lattice relaxation time (T(1))-weighted images in phantom were also observed., (2009 John Wiley & Sons, Ltd.)

Electrical field treatment (EFT) using alternating current was investigated for the possibility that it could enhance the out‐of‐plane effective thermal conductivity (TC) of carbon nanofiber (CNF)/polymer composite sheets with high concentrations of filler. Two types of polymers were used as the base: fluorinated polyimide (PI) and silicone rubber. For the CNF/fluorinated PI, the influence of frequency was clarified at 2 kV of amplitude voltage when using a CNF concentration up to 15.0 vol%. As a result, the effective TC was clearly increased by EFT, and the degree of the enhancement of effective TC was obviously greater at 0.01 Hz than at either 100 or 1 × 106 Hz. Moreover, the effective TCs of two types of CNF/silicone rubber were also enhanced by EFT with 2 kV and 0.01 Hz for concentrations of CNF up to 5.2 vol%, although there is a large difference in the preparation methods between CNF/fluorinated PI and CNF/silicone rubber. Furthermore, the tensile strength of the sheets prepared with EFT implied a change in the orientational structure of CNF inside the silicone rubber matrix, although the effect of EFT on the tensile strength was smaller compared with that on the effective TC. [ABSTRACT FROM AUTHOR]

A new hyperbranched electrochromic (EC) polymer containing many viologen units was developed. The EC polymer film was easily fabricated by a spin coating method and employed as thin EC display film. All-solid EC display was constructed with polymeric electrolyte gel and hyperbranched polymer. The EC display was operated with good contrast and rapid response at low bias voltage, 2.5 V. [ABSTRACT FROM AUTHOR]

A hyperbranched polymer containing high concentrations of viologen units was employed to sensitively detect serotonin. The formation of CT complex between hyperbranched viologen polymer, HB-1 and serotonin was investigated by UV-visible absorption and fluorescence spectroscopy as a function of serotonin concentration in the absence and presence of L-tryptophan as a possible disturbing agent. Serotonin was sensitively and selectively detected down to 2 μM in aqueous solutions even in the coexistence of L-tryptophan. [ABSTRACT FROM AUTHOR]

The article focuses on the synthesis of the dimension of a hyberbranched polymer from a derivative of styrene. It states that branched polymers often will have smaller dimensions than corresponding linear polymers that have the same degree of polymerization, and that this makes processing of production easier due to the reduced solution viscosity. It mentions that by photopolymerizing N,N-diethylamino dithiocarbamoylmethylstyrene, a hyberbranched polymer can be synthesized in a one-pot reaction scheme.

A novel approach to surface modification of polymer films is proposed on the basis of graft polymerization initiated from photosensitizers attached to hyperbranched polymers which are localized at the film surface. [ABSTRACT FROM AUTHOR]

An abstract of the article "Synthesis and Catalysis of B12-Core-Shell Hyperbranched Polymer," by Hisashi Shimakoshi and colleagues is presented.