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PREPARATION OF MULTIFUNCTIONAL ORGANOLITHIUM INITIATOR IN CYCLOHEXANE SOLUTIONS

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Chinese Journal of polymer Science 2011年第4期29卷 431-438页

作者：张必英 The Key Laboratory of Beijing City on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology

Multifunctional organolithium initiator was prepared in cyclohexane solvent. The process started with adding the cyclohexane solution of butadiene to naphthalene-lithium in batches to produce butadiene oligomer dilithium with 4-8 butadiene repeating units. In the first feeding, the maximum loading of cyclohexane and the minimum concentration of butadiene cyclohexane solution must be controlled under Vcyclohexane 〈 1.33 VTHF and p 〉 40.6cN. Then, SnCl4 was added and eventually the multifunctional organolithium initiator containing Sn atom was synthesized through coupling reaction. Experiment results showed that adding the cyclohexane solution in batches was effective in overcoming some difficulties, such as insolubility of naphthalene-lithium in cyclohexane, low efficiency of naphthalene-lithium in initiating butadiene. In practice, benzene can be replaced by cyclohexane completely, which can not only reduce environmental pollution from benzene, but also overcome the difficulty of solvent recovery caused by similar boiling point between benzene and cyclohexane. Prepared with multifunctional organolithium containing Sn atom as initiator, the star-shaped solution polymerized styrene-butadiene rubber （star S-SBR） with better vulcanization performances, lower rolling resistance and higher wet-skid resistance was obtained.

关键词： Multifunctional organolithium initiator Anionic polymerization Cyclohexane Star S-SBR.

The performance enhancement in organic light-emitting diode using a semicrystalline composite for hole injection

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Chinese Physics B 2008年第7期17卷 2725-2729页

作者：曹峻松关敏曹国华曾一平李晋闽秦大山 novel Materials Laboratory Institute of SemiconductorsChinese Academy of Sciences Institute of polymer Science and Engineering Hebei University of Technology

A semicrystalline composite, 3, 4, 9, 10 perylenetetracarboxylic dianhydride （PTCDA） doped N,N＇-di（1-naphthyl）- N,N＇-diphenylbenzidine （NPB）, has been fabricated and characterized. An organic light-emitting diode using such a composite in hole injection exhibits the improved performance as compared with the reference device using neat NPB in hole injection. For example, at a luminance of 2000 cd/m2, the former device gives a current efficiency of 2.0cd/A, higher than 1.6cd/A obtained from the latter device. Furthermore, the semicrystalline composite has been shown thermally to be more stable than the neat NPB thin film, which is useful for making organic light emitting diodes with a prolonged lifetime.

关键词： semicrystalline composite hole injection organic light-emitting diode

Synthesis and characterization of miktoarm star copolymer of styrene and butadiene using multifunctional macromolecular initiator

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Chinese Chemical Letters 2009年第9期20卷 1131-1135页

作者： Hai Yan Zhang Xing Ying Zhang Key Laboratory on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology Beijing 100029 China

A new kind of multifunctional macromolecular initiator with Sn-C bonds and polydiene arms was synthesized by living anionic polymerization. At first, polydiene-stannum chloride （PD-SnCl3） was prepared by the reaction of n-butyl-Li （n-BuLi）, stannic chloride （SnCl4） and diene. Then PD-SnCl3 was used to react with the dilithium initiator to prepare the multifunctional organic macromolecular initiators. The result suggested that the initiators had a remarkable yield by GPC, nearly 90%. By using these multifunctional macromolecular initiators, styrene and butadiene were effectively polymefized via anionic polymerization, which gave birth to novel miktoarm star copolymers. The relative molecular weight and polydispersity index, microstructure contents, copolymerization components, glass transition temperature （Tg） and morphology of the miktoarm star copolymers were investigated by GPC-UV, ~H NMR, DSC and TEM, respectively. 2009 Xing Ying Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Mnitifunctional macromolecular initiator Miktoarm star copolymer Styrene Butadiene Isoprene Anionic polymerization

Simultaneous Functionalization and Reduction of Graphene Oxide with Polyetheramine and Its Electrically Conductive Epoxy Nanocomposites

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Chinese Journal of polymer Science 2014年第8期32卷 975-985页

作者： Gongqing Tang Zhi-Guo Jiang Xiaofeng Li 张好斌于中振 State Key Laboratory of Organic-Inorganic Composites Department of Polymer Engineering College of Materials Science and Engineering Beijing University of Chemical Technology Beijing Key Laboratory on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology

Simultaneous functionalization and reduction of graphene oxide （GO） is realized by refluxing of GO suspension with polyetheramine （D2000） followed by thermal treatment at 120℃. Compared to GO, the D2000-treated GO （GO- D2000） becomes hydrophobic, thermally stable and highly conductive with an electrical conductivity of 11 S/m, which is almost 8 orders of magnitude higher than that of GO. Due to the high conductivity and improved dispersion of GO-D2000, its epoxy nanocomposites exhibit a sharp transition from electrically insulating to conducting with a low percolation threshold of 0.71 vol%. With 3.6 wt% GO-D2000, the glass transition temperature of the epoxy nanocomposite is 27 K higher than that of neat epoxy.

关键词： Graphene oxide Epoxy Chemical reduction Electrical conductivity Glass transition temperature.

Macroporous Titania Monolith Prepared via Sol-gel Process with polymer Foam as the Template

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Chinese Journal of Chemistry 2006年第7期24卷 955-960页

作者：任剑杜中杰张晨励杭泉 The Key Laboratory of Beijing City on Preparation and Processing of novel polymer Materials at Beijing University of Chemical technology Beijing 100029 China

Macroporous titania monoliths were prepared via sol-gel method using polymer foam as templates. The polymer foam polymerized via concentrated emulsion polymerization was immerged in a solution of titanium（Ⅳ） isopropoxide in 2-propanol, which underwent a sol-gel process. The organic components were subsequently removed by calcination. The effects of various parameters, including the nature of the monomer, the volume fraction of dispersed phase of the concentrated emulsion, and concentration of the sol-gel solution were investigated. The SEM micrographs of the macroporous titania monoliths thus obtained showed that the porous structure of the final material was effectively controllable.

关键词： porous metal oxide sol-gel macroporous titania monolith concentrated emulsion polymerization

Physical dispersion state and fluorescent property of Eu-complex in the Eu-complex/silicon rubber composites

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Journal of Rare Earths 2008年第5期26卷 626-632页

作者：温世鹏胡水张小萍张立群刘力 Key Laboratory of Beijing City on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology Key Laboratory for Nanomaterials Ministry of Education Beijing University of Chemical Technology

The fluorescent complex Eu（TTA）2（Phen）（MA）（HTTA=2-Thenoyltrifluoroacetone, Phen=1,10-phenanthroline, MA=Maleic an- hydrider） was synthesized and characterized with elemental analysis, infrared spectrum （IR）, scanning electron microscope （SEM）, X-ray Diffraction（XRD）, differential scanning calorimetry（DSC）, and fluorescent measurement. To explore the effect of different physical dispersion state of Eu-complex on the fluorescent property of the Eu-complex/silicon rubber composites, various quantifies of Eu（TTA）2（phen）（MA） were mixed with silicon rubber （SIR） and peroxide to form uncured composites. These composites were vulcanized to obtain cured Eu-complex/SiR composites at 250 ℃, which was higher than the melting-point of Eu-complex. The SEM, XRD, DSC, and the fluorescent measurement of these composites showed that both the complex molecules dispersed in the silicon rubber during the melting process and the parent Eu-complex particles had positive effects on fluorescent property, whereas the re-crystallized Eu-complex particles and the aggregating complexes formed during the melting-process had negative effects on fluorescent property. For the uncured composites, their fluorescent intensities almost did not change with the increasing amount of Eu-complex. Furthermore, for the composites with small content of Eu-complex, their fluorescent intensities decreased significantly after curing, and this difference in fluorescent intensity became smaller as the content of Eu-complex increases.

关键词： polymer-matrix composites melting blending physical dispersion state fluorescent property rare earths

Covalent Functionalization of Multiwalled Carbon Nanotubes with Poly（acrylic acid）

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Chinese Journal of Chemistry 2006年第4期24卷 563-568页

作者：刘演新杜中杰李艳张晨励杭泉 The Key Laboratory of Beijing City on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology Beijing 100029 China

Covalent functionalization of multiwalled carbon nanotubes （MWNT） with poly（acrylic acid） has been successfully achieved via grafting of poly（acryloyl chloride） on nanotube surface by esterification reaction of acyl chloride-bound polymer with hydroxyl functional groups present on acid-oxidized MWNT and hydrolysis of polymer attached to nanotubes. polymer-functionalized MWNT could possess remarkably high solubility in water, and their aqueous solution was very stable without any observable black deposit for a long time. Characterizations of such functionalized MWNT samples using Fourier transform infrared spectrometer, transmission electron microscopy and nuclear magnetic resonance techniques indicated that poly（acrylic acid） was covalently attached to the surface of MWNT.

关键词： multiwalled carbon nanotube oxidation functionalization poly(acrylic acid)

Fluorescence and Judd-Ofelt analysis of rare earth complexes with maleic anhydride and acrylic acid

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Journal of Rare Earths 2008年第6期26卷 787-791页

作者：温世鹏张小萍胡水张立群刘力 Key Laboratory of Beijing City on Preparation and Processing of novel polymer Materials Beijing University of Chemical Technology Key Laboratory for Nanomaterials Ministry of Education Beijing University of Chemical Technology

Two kinds of Eu-complexes, Eu（TTA）2（Phen）（AA） and Eu（TTA）2（Phen）（MA）（HTTA=2-Thenoyltrifluoroacetone, Phen=1,10- phenanthroline, AA=acrylic acid, MA=Maleic anhydride）, which combined the excellent fluorescence properties of Eu（TTA）2（Phen）（H2O） and the reactivity of acrylic acid and maleic anhydride with radicals, were synthesized. The two complexes were characterized by elemental analysis, infrared （IR） spectra, and X-ray photoelectron spectroscopy （XPS）. Based on the data shown from the fluorescent spectra of the Eu-MA and Eu-AA complexes, the Ωλ （λ=2 and 4） experimental intensity parameters were calculated. The results demonstrated that the Ω2 intensity parameters for the two complexes were smaller than those for the Eu（TTA）2（Phen）（H2O） complex, indicating that a less symmetrical chemical environment existed in the complexes. It implied that the radiative efficiency of the ^5D0 of these two complexes could be enhanced by ligand of MA and AA, respectively. The luminescent lifetime of the Eu-AA （r=-7.26×10^-4 s） or Eu-MA complex （r=-8.12×10^-4 s） was higher than that of the Eu（TTA）2（Phen）（H2O） complex, which was attributed to the substitution of the water molecule （H2O） in Eu（TTA）2（Phen）（H2O） by the MA or AA ligand.

关键词： organic ligands XPS spectra Judd-Ofelt theory rare earths

Preparation and characterization of gelatin/cerium(Ⅲ) film

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Journal of Rare Earths 2010年第5期28卷 756-759页

作者：黄崇军黄雅钦田娜童元建殷瑞贤 State Key Laboratory of Chemical Resource Engineering The Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials Beijing University of Chemical Technology

A novel gelatin film with antibacterial activity was prepared by electrostatic crosslinking using cerium (Ⅲ) nitrate hexahydrate as the crosslinking agent. The structure and properties of the films were investigated by Fourier transform infrared spectra, tensile tests, thermogravimetric analysis, static drop contact angle and disc diffusion method. The results showed that cross-linking could not only improve the thermal and mechanical properties and lower the hydrophilic property of the films, but also make...

关键词： gelatin/cerium (III) film antibacterial activity cross-linking rare earths