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SYNTHESIS OF A HYPERBRANCHED polyether EPOXY THROUGH ONE- STEP PROTON TRANSFER POLYMERIZATION AND ITS APPLICATION AS A TOUGHENER FOR EPOXY RESIN DGEBA

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Chinese Journal of Polymer Science 2012年第4期30卷 493-502页

作者：李效玉王海侨 Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing University of Chemical Technology State Key Laboratory of Organic-Inorganic Composites College of Materials Science and Engineering Beijing University of Chemical Technology

A novel liquid hyperbranched polyether epoxy （HBPEE） based on commercially available hydroquinone （HQ） and 1,1,1-trihydroxymethylpropane triglycidyl ether （TMPGE） was synthesized through an A2 ＋ B3 one-step proton transfer polymerization. In order to improve the toughness, the synthesized HBPEE was mixed with diglycidyl ether of bisphenol A （DGEBA） in different ratios to form hybrids and cured with triethylenetetramine （TETA）. Thermal and mechanical properties of the cured hybrids were evaluated. Results show that addition of HBPEE can improve the toughness of cured hybrids remarkably at 〈 20 wt% loading, without compromising the tensile strength. However, the glass transition temperature （Tg） of the cured hybrids decreases with increasing HBPEE content. Fracture surface images from scanning electron microscope show oriented fibrils in hybrids containing HBPEE. The formation and orientation of the fibrils can absorb energy under impact and lead to an improvement of toughness. Furthermore, based on the morphology of fractured surfaces and the single Tg in each hybrid, no sign of phase separation was found in the cured hybrid systems. As a result, the toughening mechanism could be explained by in situ homogeneous toughening mechanism rather than phase separation mechanism.

关键词： Hyperbranched Epoxy polyether Toughening Proton transfer polymerization.

IMMOBILIZATION OF POTENTIALLY BIOACTIVE MOIETIES ONTO polyether WITH POLY(ETHYLENE GLYCOL)-SULFONATE SPACER

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Chinese Journal of Polymer Science 1997年第2期15卷 180-186页

作者：计剑封麟先邱永兴俞小洁杨士林 Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

A new reactive graft copolymer, poly(tetramethylene glycol)-graft-omega-propyl sodium sulfonate-poly(ethylene glycol) (PTMG-g-PEG-CH2CH2CH2SO3-Na+), was synthesized by the cationic polymerization of alpha-omega-bifunctional PEG macromonomer ((sic)CH2-PEG-CH2CH2CH2SO3Na) and THF. The obtained copolymer exhibits the expected structure as indicated by the result of characterization. Two amino acids (L-arginine, L-tyrosine) were covalently attached to the copolymer after converting the sulfonate group, to sulfonyl chloride. So the new reactive graft copolymer (PTMG-g-PEG-CH2CH2CH2SO3-Na+) is expected to be very useful in attachment of potentially bioactive moieties to polymer via a hydrophilic PEG spacer.

关键词： potentially bioactive moieties polyether biocompatible materials

Structure dependence of intramolecular photoinduced electron transfer in 9-aminoacridine benzoyl esters dyads linked by a polyether chain

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Chinese Science Bulletin 1997年第19期42卷 1619-1624页

作者： Li, SL Tian, HJ Zhou, QF Li, ZH Xu, HJ CHINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

ELECTRON transfer plays a crucial role in energy transformation of natural biological systemssuch as the photosynthetic process by which plants convert solar energy into chemical *** is achieved in photosynthesis by a series of electron transfers which occur after light is ab-sorbed. Among the various factors which influence the efficiency of electron transfer struc-tural effect is one of the important features to be considered. In recent years, numerous syn-thetic model dyads in which electron donor and electron acceptor are covalently linked by dif-ferent spacers have been designed and synthesized in an effort to understand how the

关键词： polyether donor-acceptor dyads intramnlecular photoinduced electron transfer.

Study on EPR Spectra of Three Gadolinium Complexes With Noncyclic polyether Schiff Bases

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Science China Chemistry 1994年第2期37卷 153-161页

作者：陈德余姚克敏封子先蔡乐真周佩芬薛祺 (Department of Chemistry Zhejiang University Hangzhou 310027 PRC

The EPR spectra of three new gadolinium complexes with noncyclic polyether Schiff bases in powder and those of these complexes in organic solvents were investigated at different temperatures. It was observed that EPR spectra of nine and four peaks of Gd(Ⅲ) complexes in polycrystalline powder and freezing samples appeared at low temperature respectively for the first time. The interpretations of these results obtained on the basis of spin Hamiltonian of s = 7/2 system are satisfactory. The correlations of EPR feature between crystal-field strength in complexes and local symmetry around Gd3+ ions were revealed. The crystal-field parameters b20 and the asymmetry parameters λ’ of complexes were estimated. A series of interesting regularity and new results were obtained.

关键词： gadolinium ion noncyclic polyether Schiff base complexes EPR spectra.

A Structure-properties Study of MDI-based Hydrophilic polyether-polyester Polyurethane

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Journal of Donghua University(English Edition) 2009年第4期26卷 408-412页

作者：权衡顾振亚吴穗生 College of Chemical Engineering Wuhan University of Science and Engineering School of Textiles Tianjin Polytechnic University Guangzhou Textile Research Institute

A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and polyethylene glycol 1000 (PEG1000), with 1,4-butanediol (BDO) as the chain extender. Furthermore, several representative properties of the polyurethanes, such as moisture permeability, water resistance, hydrophilic property, and phase inversion temperature, were investigated. The studies show that the structure and concentration of soft segment have a remarkable effect on the main application properties of polyurethane. On the contrary, the functional properties of the polyurethane are almost not affected by its hard segment.

关键词： hydrophilic polyurethane polyether polyester structure property

ENHANCEMENT OF ENERGY TRANSFER FROM THE TERMINAL CHROMOPHORE OF polyether TO EUROPIUM CATION（Ⅲ）VIA C

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影像科学与光化学 1994年第3期 259-262页

作者： TUNG CHEN-HO WU LI-ZHU(The Labomtory of Photochemistry, Institute of Photapmphic Chemistry,Chinese Academy of Sctences,Beijing 100101, P.R.China)

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关键词： complexation polyether europium energy transfer

THE COORDINATION BETWEEN SILVER NITRATE AND OPEN CHAIN polyether

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中国有色金属学会会刊：英文版 1993年第1期3卷 38-41页

作者： Li, Yongxiu Ni, Zhaoai Jiangxi University, Nanchang 330047, China Hangzhou University, Hangzhou 310028, China

A complex of silver nitrate with 1.8-bis（8’-quinolyloxy）-3.6-dioxaoctane （noted as ligand L） was synthesized. The results of element analysis show that it consists of the calculated values of [Ag4L3]（NO3）4. It is clear from the IR, UV and ’HNMR spectra that the ligand L coordinated to Ag+ ion with its N and 0 atoms which connected with the terminal quinolyloxy group.

关键词： open chain polyether silver nitrate coordination

Investigation of the Mechanical Properties of Flexible polyether Foam Filled with Eggshell and Groundnut Husk Powder

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Organic Polymer Material Research 2019年第2期1卷 14-19页

作者： P.U.Chris-Okafor R.U.Arinze I.M.Iloamaeke B.C.Izundu Department of Pure and Industrial Chemistry Faculty of Physical SciencesNnamdiAzikiwe UniversityAwkaAnambra StateNigeria

The study investigated the effect of eggshell and groundnut husk as fillers on flexible polyether *** fillers with the particle sizes of 50μm each were mixed in the ratio of 50:*** percentages of the two combined fillers ranging from 10%,20%,30%,40%and 50%were incorporated into the polyether recipes in the appropriate foam formulations and foam samples were *** unfilled foam(0%filler)served as the standard control *** physico-mechanical test carried out on the foam showed increase in the properties such as density,compression set test,indentation hardness test,tensile strength test and decrease for elongation at break test as compared to the unfilled *** scanning electron microscopy result showed the cell sizes became smaller and concentrated with an irregular shape as the filler load increased,thereby making it denser and *** and groundnut husk fillers may be used in the making of flexible polyether foam since these materials are organic in *** can improve the mechanical properties and biodegradability of polyurethane *** utilization of these fillers in polymer composites productin will help in sanitizing the environment by reducing landfills and producing eco-friendly waste and also it influences cost positively.

关键词： Egg shell Groundnut husk polyether foam Scanning electron microscope Mechanical properties

Synthesis and Characterization of EO/PO Random Copolyethers

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Journal of Donghua University(English Edition) 2004年第5期21卷 60-64页

作者：郭建国苑仁旭何素芹朱诚身焦宇江建明 College of Materials Engineering Donghua University Shanghai 200051 ChinaCollege of Materials Engineering Zhengzhou University Zhengzhou 450052 China College of Materials Engineering Zhengzhou University Zhengzhou 450052 China

Ethylene oxide(EO) and propylene oxide(PO) random copolyethers were synthesized by the sequential addition of the mixture of ethylene oxide and propylene oxide to propylene glycol (initiator) in the presence of potassium hydroxide(KOH), and characterized with infrared spectrum(FTIR) and nuclear magnetism resonance(NMR). The effects of catalyst concentration, reaction temperature, charging rate and EO/PO mixture ratio on the polymerization reaction were investigated. It was revealed that the optimal reaction condition is the ratio of 2.5∶1 000(KOH mass vs. product mass), at 114.6℃ and pressure below 0.4 MPa. The residual KOH was neutralized by phosphoric acid(H 3PO 4). Then the crude copolyether was refined with adsorbents, and the refined copolyether, which contains less than 0.7 μg/ml K+, was obtained as colorless, viscous liquid.

关键词： ethylene oxide propylene oxide polyether propylene glycol