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Luminescence of RE^(3+) and energy transfer from Gd^(3+) to RE^(3+) (RE = Dy, Eu) in SrGdAlO_4:RE^(3+)

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chinese Journal of chemistry 1997年第1期15卷 60-67页

作者： LIU, Sheng-Li SU, QiangLaboratory of Rare Earth chemistry and Physics, changchun institute of applied chemistry, chinese academy of sciences, changchun, Jilin 130022, china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2, 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.

关键词： Luminescence energy transfer rare earth aluminate

Study on polymerization and structure of polydiphenylamine

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chinese Journal of chemistry 1994年第2期12卷 138-147页

作者： JIN, Wen SONG, Fa-Yi DONG, Shao-JunLaboratory of Electroanalytical chemistry, changchun institute of applied chemistry, chinese academy of sciences, changchun, Jilin 130022, china Laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent uniform polymer film which exhibits mutiple colour variation(yellow-green-blue) in a wide range of potential scan. The polymerization mechanism and the structure of the polymer were studied by cyclic voltammetry, FT-IR and in situ ESR. The results indicate that the electrochemical polymerization of diphenylamine belongs to a cationic radical polymerization process. During electrolysis, only oligomers were initialy produced, then polymer film was formed on the electrode surface. The electropolymerization performs via the 4,4' C-C phenyl-phenyl coupling mechanism.

关键词： DPA electrochemical polymerization mechanism ESR.

Luminescent properties of Ba_3(PO_4)_2:Eu,Tb phosphors

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chinese Journal of chemistry 1996年第5期14卷 399-403页

作者： GAO,Yong SHI,Chun-ShanLaboratory of Rare Earth chemistry and Physics,changchun institute of applied chemistry,chinese academy of sciences,changchun,Jilin 130022,china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2:Eu,Tb phosphors which are synthesized in air *** valence state of europium is influenced by amount of *** is notable that the relative intensity of the emission spectra peaks corresponding to Eu2+ is increased if the amount of Tb3+ is *** phenomena can be explained by an electron transfer *** predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2 matrix.

关键词： Luminescence europium terbium phosphor

MECHANISM-TRANSFORMATION SYNTHESIS AND CHARACTERIZATION OF POLY(STYRENE-b-2-ETHYL-2-OXAZOLINE) DIBLOCK COPOLYMER

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chinese Journal of Polymer Science 1999年第2期17卷 145-150页

作者： Sheng-qing Xu Han-ying Zhao Tao Tang Bao-tong Huang changchun institute of applied chemistry, chinese academy of sciences, changchun 130022, china 中科院长春应用化学所吉林长春

By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution.

关键词： diblock copolymer mechanism-transformation polymerization 2-ethyl-2-oxazoline styrene characterization

KINETICS STUDY ON MELT GRAFTING ACRYLIC ACID ONTO LLDPE USING REACTIVE EXTRUSION

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chinese Journal of Polymer Science 2005年第6期23卷 603-610页

作者： Qiang Shi Lian-chao Zhu Chuan-lun Cai and Jing-hua Yin State Key Laboratory of Polymer Physics and chemistry,changchun institute of applied chemistry,chinese academy of sciences,changchun 130022,china State Key Laboratory of Polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The kinetics of melt grafting acrylic acid （AA） onto linear low density polyethylene （LLDPE） by using reactive extrusion was investigated. The polymeric peroxides （POOP and POOH） generated by electron beam irradiation were used to initiate the graft reaction. The samples taken out from the barrel at five ports along screw axis were analyzed by FTIR. The spectra show that both the graft copolymerization and homopolymerization proceed in two stages： the graft degree （or mass of homopolymer） increases linearly with the reaction time in the initial stage, and then gradually in the second stage. The rate of graft copolymerization Rg is always faster than that of homopolymerization Rh in the present system and the activation energy is 131 kJ · mol^-1 for graft copolymerization and 127 kJ · mol^-1 for homopolymeirzation. These results were interpreted in terms of solubility and diffusion of monomer, as well as the reactivity and the concentration of reactive species. The relationships between reaction rate and monomer concentration and peroxide concentration were found to be： Rg ∞ [M]^1.46[POOP＋POOH]^0.53 and Rh ∞ [M] ^1.08[POOH]^0.51, which indicate that the addition of monomer to polymeric radicals is a slow step for the graft copolymerization.

关键词： Graft copolymerization Kinetics Reactive extrusion

SYNTHESIS AND CHARACTERIZATION OF NOVEL BIPOLAR PPV-BASED COPOLYMER CONTAINING TRIAZOLE AND CARBAZOLE UNITS

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chinese Journal of Polymer Science 2001年第6期19卷 615-621页

作者： Ze Liu Li-xiang Wang Xia-bin Jing Fo-song Wang The State Key Laboratory of Polymer Physics and chemistry changchun institute of applied chemistry chinese academy of sciences, changchun 130022, china 中科院长春应用化学所高分子物理与化学国家重点实验室吉林长春

Two new blue light-emitting PPV-based conjugated copolymers containing both an electron-withdrawing unit (triazole-TAZ) and electron-rich moieties (carbazole-CAR and bicarbazole-BCAR) were prepared by Wittig condensation polymerization between the triazole diphosphonium salt and the corresponding dialdehyde monomers. Their structures and properties were characterized by FT-IR, TGA, DSC, UV-Vis, PL spectroscopy and electrochemical measurements. The resulting copolymers are soluble in common organic solvents and thermally stable with a T-g of 147degreesC for TAZ-CAR-PPV and of 157degreesC for TAZ-BCAR-PPV. The maximum photoluminescence wavelengths of TAZ-CAR-PPV and TAZ-BCAR-PPV film appear at 460 nm and 480 nm, respectively. Cyclic voltammetry measurement demonstrates that TAZ-BCAR-PPV has good electrochemical reversibility, while TAZ-CAR-PPV exhibits the irreversible redox process. The triazole unit was found to be an effective pi-conjugation interrupter and can play the rigid spacer role in determining the emission colour of the resulting copolymer.

关键词： light-emitting polymer PPV-based bipolar polymer triazole-containing polymer carbazole-containing polymer

STUDIES ON THE INTERFACIAL ADHESION BETWEEN FUNCTIONALIZED POLYPROPYLENE AND POLYAMIDE 1010

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chinese Journal of Polymer Science 1999年第3期17卷 237-244页

作者： Xiao-min Zhang Zhihui Yin Yongxian Song Jinghua Yin Polymer Physics Laboratory, changchun institute of applied chemistry, chinese academy of sciences, changchun 130022, china 中科院长春应用化学所高分子物理及化学国家重点实验室吉林长春 130022 中科院长春应用化学所高分子物理及化学国家重点实验室吉林长春

The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.

关键词： polyamide 1010 polypropylene-g-GMA interface behavior adhesion

Monte Carlo simulation on kinetic behavior of one-pot hyperbranched polymerization based on AA*+CB_2

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Science china chemistry 2010年第12期53卷 2481-2489页

作者： ZHAN Jie,LIN Ying,LIU XiaoHui & LI YueSheng State Key Laboratory of Polymer Physics and chemistry changchun institute of applied chemistry,chinese academy of sciences,changchun 130022,china State Key Laboratory of Polymer Physics and chemistry changchun institute of applied chemistry Chinese Academy of Sciences Changchun China

Monte Carlo simulation was applied to investigate the kinetic behavior of AA*+CB2 *** algorithm consisted of two procedures to simulate the in-situ synthesis of AB2-like intermediate and the subsequent polymerization,*** order to improve the accuracy of the prediction,the mobility distinction between different scale molecules in polymerization was taken into account by relating the reaction rate constants to the collision possibility of each pair of *** feed ratio of initial monomers and the activity difference between the two functional groups within AA* were studied systematically to catch the essential features of the *** results have revealed that the achievable maximum conversion primarily depends on the extent of the reactivity difference between A and A*-groups,and it is suggested that A*-group should be at least 10 times more active than A-group to achieve high number-average degree of polymerization.

关键词： Monte Carlo hyperbranched kinetic AA+CB2

Polyfluorenes containing pyrazine units:Synthesis,photophysics and electroluminescence

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Science china chemistry 2011年第4期54卷 656-665页

作者： WANG Ming,LI Ying,XIE ZhiYuan & WANG LiXiang State Key Laboratory of Polymer Physics and chemistry changchun institute of applied chemistry,chinese academy of sciences,changchun 130022,china State Key Laboratory of Polymer Physics and chemistry changchun institute of applied chemistry Chinese Academy of Sciences Changchun China

A series of conjugated copolymers of 9,9-dioctylfluorene and symmetrical pyrazine unit (BY) were synthesized by Suzuki copolymerization and were used as novel light-emitting materials in *** energy transfer was observed in both thin film and *** with the lowest occupied molecular orbital (LUMO) energy level of the polyfluorenes homopolymer (PFO),the lower LUMO energy levels of copolymers indicated that the introduction of the BY unit would be benefit to electron *** turn-on voltages of their single-layer electroluminescent (EL) devices (ITO/PEDOT/polymer/LiF/Al) were at 6.1-4.0 V,which were much lower than that of PFO (7.0 V).The maximum brightness,current efficiency,and external quantum efficiency of all PFBY copolymers were higher than those of the PFO *** single-layer device of PFBY5 was the best one in the copolymers,with a maximum brightness of 485 cd/m2,a current efficiency of 0.29 cd/A,and an external quantum efficiency of 0.10%.The introduction of PVK and TPBI for the multilayer device of PFBY5 increased the device efficiencies,which showed a maximum brightness of 3012 cd/m2,a maximum current efficiency of 1.81 cd/A,and an external quantum efficiency of 0.66%.

关键词： pyrazine polyfluorenes energy transfer PLED