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β-Phase Crystallization of Poly(vinylidene fluoride) in Poly(vinylidene fluoride)/Poly(ethyl methacrylate) Blends

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Chinese Journal of Polymer Science 2019年第1期37卷 94-100,4-7页

作者： Zi-Jie Huang Jing Jiang gi xue Dong-Shan Zhou Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Key Laboratory of High Performance Polymer Materials and Technology and The State Key Laboratory of Coordination Chemistry Nanjing University School of Physical Science and Technology Xinjiang Key Laboratory and Phase Transitions and Microstructures in Condensed Matters Yili Normal University

The nature of the crystalline phase of poly(vinylidene fluoride)(PVDF) in compatible blends with poly(ethyl methacrylate)(PEMA) was investigated by using X-ray diffraction(XRD), infrared microscopy(IR) and differential scanning calorimetry(DSC). The βphase of PVDF was observed after quenching from the melt and further annealing above the glass transition temperature over a composition range. The PVDF/PEMA blend with weight ratio of 3:2 has formed higher content of PVDF β crystals than others. By taking advantage of fast cooling rate of ultrafast differential scanning calorimeter(UFDSC), the quenching process of blends was modeled and tested simultaneously, and the melting behavior of β crystals in all blends was investigated. Three types of crystallization behavior of βphase PVDF in blends were found after quenching-annealing at different temperatures.

关键词： β-Crystal of PVDF Mesophase PVDF/PEMA blend Ultra-fast scanning calorimetry

Facile and Controllable Assembly of Multiwalled Carbon Nanotubes on Polystyrene Microspheres

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Chinese Journal of Polymer Science 2014年第6期32卷 711-717页

作者：李云兴 Yan Gao Cheng Yang Zhao-qun Wang gi xue The Key Laboratory of Food Colloids and Biotechnology Ministry of Education School of Chemical and Material Engineering Jiangnan University Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Nanjing University

Herein a facile and controllable heterocoagulation between polystyrene （PS） microspheres and multiwalled carbon nanotubes （MWCNTs） is introduced based on colloid thermodynamics. The MWCNTs play the role of steric stabilizer for stabilizing the metastable PS microspheres and thus immobilize spontaneously on the surface of PS microspheres. The synthesized MWCNTs-coated PS composite particles have been extensively characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetry and Raman spectroscopy. The results indicate that the structure and morphology of the resultant MWCNTs-coated PS composite particles are significantly affected by the weight ratio of PS and MWNCTs and the amount of poly（vinylpyrrolidone） that is injected into PS dispersion before they are mixed with MWCNTs. Therefore, these composite particles have the potential to produce MWCNTs-based composite materials with controllable mass loading and dispersity of MWCNTs.

关键词： Multiwalled carbon nanotube Polystyrene microsphere Heterocoagulation Structural control Colloidthermodynamics.

IMPEDANCE CHARACTERISTICS OF POLYFURAN FILMS

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Chinese Journal of Polymer Science 2002年第5期20卷 419-423页

作者： Liang Li Xiao-bo Wan gi xue Department of Polymer the State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093. China Nanjing Univ Dept Polymer State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

Electrochemical impedance spectroscopy (EIS) was first used for the characterization of polyfuran (PFu) films that had been formed electrochemically on an Au electrode. The polyfuran was measured in high oxidation state, intermediate oxidation state and reduction state, respectively. As the oxidation level is increased, the ionic conductivity of PFu/BF4- increases. And impedance studies on PFu show that the anion BF4- appears to be mobile with a high diffusion coefficient of approximately 10(-8) cm(2).s(-1).

关键词： polyfuran electrochemical impedance spectroscopy capacitance

A FOURIER TRANSFORM INFRARED SPECTROSCOPIC STUDY OF THE REACTION BETWEEN POLY (VINYL PYRIDINE)S AND EPOXY COMPOUNDS

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Chinese Journal of Polymer Science 1987年第2期5卷 133-140页

作者：薛奇江善根 Department of Chemistry Nanjing University Nanjing Department of Chemistry Nanjing University Nanjing

Chemical reactions between poly （vinyl pyridine）s and 1, 4-butanediol diglycidyl ether and other epoxy compounds were studied by Fourier transform infrared spectroscopy and other techniques. The epoxy group was found to react with the pyridine side group of poly （4-vinyl pyridine）, forming crosslinked networks which contain cyclic amide structures. The reaction was also observed in the interracial region of poly（vinyl pyridine） and γ-glycidoxy propyl trimethoxysilane hydrolyzate （γ-GPS） coatings on PET fiber substrates. Poly（2-vinyi pyridine） does not show the same reaction.

关键词： poly(4-vinyl pyridine) poly(2-vinyl pyridine) epoxy, compound cyclic amide FTIR PET fiber interfacial reaction

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高分子链的去拥挤转变及低温流动

高分子学报 2011年第9期21卷 1001-1006页

作者：滕超薛奇南京大学化学化工学院高分子科学与工程系南京微结构国家实验室(筹) 南京210093

简述了拥挤理论的基本原理,运用拥挤理论来说明高分子链间弱相互作用对高分子链所处的状态的影响,特别是对高分子玻璃化转变的影响.在实验中,采用固体核磁共振方法探测高分子的链间邻近度,并比较了不同链间邻近度的高分子样品在玻璃化... 详细信息

简述了拥挤理论的基本原理,运用拥挤理论来说明高分子链间弱相互作用对高分子链所处的状态的影响,特别是对高分子玻璃化转变的影响.在实验中,采用固体核磁共振方法探测高分子的链间邻近度,并比较了不同链间邻近度的高分子样品在玻璃化转变温度以下的压力诱导流行行为,发现即使测试温度比高分子玻璃化转变温度低132℃,高分子链在压力下依然可以进行局部流动,即高分子链的低温流动行为.拥挤理论为高分子链的低温流动行为提供了依据,并为玻璃化转变的机理提供了新的解释.与此同时,高分子链的低温流动也为高分子加工提供了新的思路和方法.

关键词：高分子链低温流动去拥挤转变高分子加工玻璃化转变

Several New Examples Concerning SERS Studies of Polymers

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Several New Examples Concerning SERS Studies of Polymers

Probing the Two-stage Transition upon Crossing the Glass Transition of Polystyrene by Solid-state NMR

第十三届全国光散射学术会议

作者： Yun Lu gi xue Department of Polymer Science and Engineering College of Chemistry and Chemical EngineeringNanjing University

＜正＞Surface enhanced Raman scattering（SERS）is a very ideal and effective in situ analytical technique for the study of microstructure of polymer-metal interfaces since it enhances almost exclusively the firstmonolayer of molecules adjacent to the surface.（1）.Microstructure of high quality conductive polythiophene film.A free-standing polythiophene film had been prepared by using a low-potential electrochemically polymerization in boron-fluorideethyl

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Chinese Journal of Polymer Science 2016年第4期34卷 446-456页

作者： Yong-jin Peng Chen-ting Cai Rong-chun Zhang Tie-hong Chen 孙平川李宝会 Xiao-liang Wang gi xue An-Chang Shi School of Physics Nankai University Tianjin 300071 China Key Laboratory of Functional Polymer Materials of Ministry of Education and College of Chemistry Nankai University and Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071 China Department of Polymer Science and Engineering The School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China Department of Physics and Astronomy McMaster University Hamilton Ontario L8S 4M1 Canada

A two-stage transition upon crossing the glass transition of polystyrene with increasing temperature was precisely determined and interpreted by using solid-state nuclear magnetic resonance （SSNMR）, 1H-XH dipolar couplings based double quantum-filtered （DQF） and dipolar filter （DF） experiments and 13C chemical shift anisotropy （CSA） based centerband-only detection of exchange （CODEX） experiment are used to fully characterize the time scale of molecular motions during the glass transition. While differential scanning calorimetry （DSC） and CODEX experiment predicted the first stage of glass transiton, DQF and DF experiments provided the evidence for the second stage transition during which the time scale of molecular motions changed from very slow （t 〉 ms） to very fast （t 〈 Its）. The first stage of glass transition begins with the occurrence of remarkable slow re-orientation motions of the polymer backbone segments and ends when the degree of slow motion reaches maximum. The onset and endpoint of the conventional calorimetric glass transition of polystyrene can be quantitatively determined at the molecular level by SSNMR. In the second stage, a subsequent dramatic transition associated with the melting of the glassy components was observed. In this stage liquid-like NMR signals appeared and rapidly increased in intensity after a characteristic temperature Tf （-1.1Tg）. The signals associated with the glassy components completely disappeared at another characteristic temperature Tc （-1.2Tg）.

关键词： Glass transition Polystyrene Heterogeneous dynamics Solid-state NMR.

PARTIALLY DISENTANGLEMENT OF MONO-DISPERSED POLYPROPYLENE AND ITS PROPERTY IN THE MELT

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PARTIALLY DISENTANGLEMENT OF MONO-DISPERSED POLYPROPYLENE AN...

THE STUDIES OF THE CURING OF AN EPOXY RESIN ON COPPER WIRE BY FTIR EXTERNAL REFLECTION SPECTROSCOPY

International Symposium on Engineering Plastics EP’2001 Beijing

作者： Qing Sun gi xue Youliang Hu Department of Polymer Science & Engineering Nanjing University State Key Laboratory of Engineering Plastics

＜正＞In general,polymer chains are in the state of *** is well known that entanglement is important in determining rheological and dynamic properties of *** solution theory indicates that there is an overlap concentr...

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Chinese Journal of Polymer Science 1988年第1期6卷 51-55页

作者：薛奇刘石英江善根 Department of Chemistry Nanjing University Nanjing

The epoxy coating on copper wire has been studied by a modified sampling technique using Fourier transform infrared (FTIR) diffuse reflectance attachment. As the wire axis was parallel to the incident plane, a reflection spectrum of thin layer coating on a copper wire can be obtained. The study found that imidszole, especially the acetic acid treated imidazole, can be used as an effective curing catalyst of the epoxy resin on copper. This is the first report about the IR study of coatings on metal wires.

关键词： Reflection absorption diffuse reflectance copper wire epoxy resin imidazole curing.