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Pyrolysis-Gas Chromatography/Mass Spectrometry for Microstructure and Pyrolysis Pathway of Polyester-Polyether Multiblock Copolymer
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作者 罗爱芹 叶玲 +2 位作者 傅若农 谢桂阳 王显伦 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期45-50,共6页
The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/M... The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/MS). PGC was applied to study the F t curve of the multiblock copolymer and PGC/MS was used to separate and identify the pyrolyzates. DTA experiment was used to study the decomposition temperature. The results show that the beginning point of elastomer’s decomposition was about 300?℃ and the decomposition temperature of most of the sample was 550?℃. Many pyrolyzates were produced because of the breaking of weak bonds in the sample. The possible microstructure was verified and the pyrolysis pathway of the copolymer was investigated. 展开更多
关键词 thermoplastic elastomer polyester polyether multiblock copolymer pyrolysis gas chromatography/mass spectrometry copolymer pyrolysis pathway MICROSTRUCTURE pyrolyzates
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Synthesis and evaluation of an oil-soluble viscosity reducer for heavy oil 被引量:27
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作者 Guo Jixiang Wang Heyi +2 位作者 Chen Chaogang Chen Yun Xie Xiaohai 《Petroleum Science》 SCIE CAS CSCD 2010年第4期536-540,共5页
To reduce the viscosity of highly-viscous oil of the Tahe oilfield (Xinjiang,China),an oilsoluble polybasic copolymer viscosity reducer for heavy oil was synthesized using the orthogonal method.The optimum reaction ... To reduce the viscosity of highly-viscous oil of the Tahe oilfield (Xinjiang,China),an oilsoluble polybasic copolymer viscosity reducer for heavy oil was synthesized using the orthogonal method.The optimum reaction conditions are obtained as follows:under the protection of nitrogen,a reaction time of 9 h,monomer mole ratio of reaction materials of 3:2:2 (The monomers are 2-propenoic acid,docosyl ester,maleic anhydride and styrene,respectively),initiator amount of 0.8% (mass percent of the sum of all the monomers) and reaction temperature of 80 oC.This synthesized viscosity reducer is more effective than commercial viscosity reducers.The rate of viscosity reduction reached 95.5% at 50 oC.Infrared spectra (IR) and interfacial tensions of heavy oil with and without viscosity reducer were investigated to understand the viscosity reduction mechanism.When viscosity reducer is added,the molecules of the viscosity reducer are inserted amongst the molecules of crude oil,altering the original intermolecular structure of crude oil and weakening its ability to form hydrogen bonds with hydroxyl or carboxyl groups,so the viscosity of crude oil is reduced.Field tests of the newly developed oil-soluble viscosity reducer was carried out in the Tahe Oilfield,and the results showed that 44.5% less light oil was needed to dilute the heavy oil to achieve the needed viscosity. 展开更多
关键词 oil-soluble viscosity reducer heavy oil SYNTHESIS EVALUATION
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Determination of Three Kinds of Polyether Drug Residues in Eggs by QuEChERS dSPE EMR-Lipid-LC/MS/MS 被引量:6
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作者 Guodong ZANG Jingwen FU +2 位作者 Qinzhan YANG Zijing HUANG Mengjun CHEN 《Agricultural Biotechnology》 CAS 2018年第1期120-122,共3页
[Objectives] This study was conducted to establish an LC-MS/MS method for the determination of three kinds of polyether residues in eggs with QuEChERS dSPE EMR-Lipid as a pretreatment method, which was established acc... [Objectives] This study was conducted to establish an LC-MS/MS method for the determination of three kinds of polyether residues in eggs with QuEChERS dSPE EMR-Lipid as a pretreatment method, which was established according to Agilent Bond Elut enhanced lipid removal EMR-Lipid technology. [ Methods] Egg was extracted by acidified acetonitrile, purified by Bond Elut EMR-Lipid QuEChERS, and detected by HPLC-MS/MS. [ Results] The three kinds of polyether residues had good linear relationships in the range of 2.0 - 100 μg/L with peak areas, r 〉 0. 999. The recoveries ranged from 84.6% to 107.0%. [ Conclusions ] The method is convenient and accurate, and the quantitative results are accurate and reproducible. It is suitable for the determination of the three kinds of polyether residues in eggs. 展开更多
关键词 QUECHERS EMR-Lipid Liquid phase tandem mass spectrometry polyetherS
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Hydrogenation of SBS Catalyzed by Immobilized Ru-TPPTS Complex in Polyether Molten Salt 被引量:1
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作者 LiWEI JingYangJIANG YanHuaWANG ZiLinJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期338-340,共3页
Catalytic hydrogenation of SBS was performed for the first time in polyether molten salt with Ru/TPPTS complex as catalyst. Experimental results showed that the hydrogenation degree can be enhanced significantly by th... Catalytic hydrogenation of SBS was performed for the first time in polyether molten salt with Ru/TPPTS complex as catalyst. Experimental results showed that the hydrogenation degree can be enhanced significantly by the addition of triphenylphosphine (TPP). When the molar ratio of TPP, TPPTS and Ru is 2:5:1, 89% hydrogenation degree can be achieved after 12 h under reaction conditions of 5.0 MPa and 150°C. The ionic liquid containing catalyst can be reused three times without obvious changes in the catalytic selectivity and activity. 展开更多
关键词 HYDROGENATION SBS ruthenium complex polyether molten salt.
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Novel Silica Gel Supported Polyether Ionic Liquids: Efficient Catalysts Applied in Transformation of Carbon Dioxide 被引量:1
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作者 Guo Liying Jin Xianchao +1 位作者 Wang Yirong Wang Haozhi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第4期60-66,共7页
Three new catalysts based on the silica gel supported polyether ionic liquids(ILs), i.e., [HO-PECH-MIM]ClSi, [H2N-PECH-MIM]Cl-Si, and [HOOC-PECH-MIM]Cl-Si, were prepared, and their chemical structures were characteriz... Three new catalysts based on the silica gel supported polyether ionic liquids(ILs), i.e., [HO-PECH-MIM]ClSi, [H2N-PECH-MIM]Cl-Si, and [HOOC-PECH-MIM]Cl-Si, were prepared, and their chemical structures were characterized by infrared(IR) spectroscopy and nuclear magnetic resonance(NMR) spectroscopy. Thermogravimetric analyzer(TG), X-ray diffractometer(XRD) and scanning electron microscope(SEM) were used to evaluate their thermal stability,crystalline structure and apparent morphology, respectively. Surface areas of the prepared catalysts were calculated by the Brunauer-Emmett-Teller(BET) method. The catalytic reaction for the synthesis of propylene carbonate(PC) using CO_2 and propylene oxide(PO) in the presence of the prepared catalysts was studied. The influences of times of recycling and catalyst structure on catalytic performance were also investigated. The experimental results showed that the silica gel supported polyether ILs catalysts successfully prepared under mild condition could possess the advantages of high activity, excellent thermal stability, good selectivity and easy recycling, while the phase transition of the liquid polyether ILs catalysts was also achieved. When the reaction temperature was 90 °C, the CO_2 pressure was 2.0 MPa and the dosage of the catalyst was 2.5%, [HOOC-PECH-MIM]Cl-Si was found to have the best catalytic performance in the catalytic process, with the conversion rate reaching 100% and the selectivity equating to 98.2%. The conversion rate and selectivity still could reach more than 90% even after the catalyst was reused for 15 times. 展开更多
关键词 .polyether IONIC liquids SILICA GEL catalyst CO2
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Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2 被引量:1
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作者 张高文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期95-99,共5页
Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy s... Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy silane(TEOS) by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2 is improved obviously and SiO2 disperses uniformly in the polymer matrix and the particle diameter of SiO2 does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2 . 展开更多
关键词 direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability
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Tribological behaviour of oil-soluble organo-molybdenum compound as lubricating additives 被引量:3
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作者 SHI Pei-jing XU Bin-shi +2 位作者 XU Yi QIAO Yu-lin LIU Qian 《中国有色金属学会会刊:英文版》 CSCD 2004年第z1期386-390,共5页
A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoD... A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoDDP and MoDTP, respectively) as additives in liquid paraffin. The morphologies of the worn surfaces and elemental distributions were observed and determined by means of scanning electron microscopy and energy dispersive spectrometry. The chemical states of some typical elements on the worn surface were analyzed on X-ray photoelectron spectroscope. The results show that MoDDP and MoDTP additives in liquid paraffin have excellent antiwear and friction-reduction properties, which are attributed to the reaction film composed of MoS2, FeS and MoO2, and the deposited film composed of phosphate on the worn surface. Moreover, these two additives have synergetic friction-reducing and antiwear effect, which is closely related to the chemical states of S on the worn surface. 展开更多
关键词 oil-soluble organo-molybdenum additive friction-reduction and antiwear behaviour TRIBOCHEMISTRY
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A Structure-properties Study of MDI-based Hydrophilic Polyether-polyester Polyurethane 被引量:1
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作者 权衡 顾振亚 吴穗生 《Journal of Donghua University(English Edition)》 EI CAS 2009年第4期408-412,共5页
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... 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. 展开更多
关键词 hydrophilic polyurethane polyether polyester structure property
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SYNTHESIS AND CHARACTERIZATION OF A FLAME RETARDANT HYPERBRANCHED POLYETHER
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作者 Jyotishmoy Borah 汪传生 Niranjan Karak 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期107-118,共12页
A brominated hyperbranched polyether has been synthesized from cyanuric chloride and sodium salt of tetrabromobisphenol-A by an A2 + B3 approach. The synthesized polyether was characterized by ^1H-NMR, ^13C-NMR, UV, ... A brominated hyperbranched polyether has been synthesized from cyanuric chloride and sodium salt of tetrabromobisphenol-A by an A2 + B3 approach. The synthesized polyether was characterized by ^1H-NMR, ^13C-NMR, UV, FTIR spectroscopy and X-ray diffraction studies, measurements of solution viscosity, molecular weight and solubility and elemental and thermogravimetric analyses. The flame retardancy of the synthesized polyether and its blends with commercially available plasticized poly(vinyl chloride) (PVC) and low density polyethylene (LDPE) was investigated by measurements of limiting oxygen index (LOI) value and thermogravimetric analysis. The properties are compared with a non-halogenated similar type of bisphenol-A based aromatic polyether after blending at different dose levels with the same base polymers. The LOI values of these blends indicated that these hyperbranched polyethers acted as flame retardant additives, and antimony trioxide had prominent synergistic effect with the bromo hyperbranched polyether for the above base polymers, and an increment of 4 to 6 units in LOI values was observed. 展开更多
关键词 Hyperbranched polyether LOI LDPE PVC.
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Alkylation of Isobutane and Isobutene in Acidic Polyether Ionic Liquids 被引量:2
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作者 Yu Fengli Gu Yulong +1 位作者 Liu Qichun Xie Congxia 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2019年第3期29-35,共7页
The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane s... The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane sultone and trifluoromethanesulfonic acid(TfOH).The prepared ILs were characterized by infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy,and their thermal stability was determined by thermal gravimetry.The synthesized polyether ILs coupled with TfOH were used to catalyze the alkylation reaction of isobutane and isobutene for the preparation of alkylate gasoline.The polyether ILs could improve the substrate dissolution and promote the separation of the catalyst from the products.The ideal IL(n=94)was determined.The optimized alkylation reaction conditions covered:a VTfOH/VIL ratio of 0.35,a reaction temperature of 40℃,a reaction time of 50 min,and a stirring speed of 800 r/min.The conversion of isobutene was 92.4%and the selectivity for the C8-product was 81.6%.Under optimal conditions,the catalyst life was determined and TfOH showed improved cyclic performance in the polyether ILs.After 8 operating cycles,the catalytic activity of the catalyst showed negligible decline. 展开更多
关键词 ALKYLATION ALKYLATE gasoline tri fluoromethanesulfonic acid polyether-based ionic liquid ISOBUTENE
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Isocyanate-terminated Polyethers Toughened Epoxy Resin:Chemical Modification,Thermal Properties,and Mechanical Strength
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作者 蔡浩鹏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第2期256-260,共5页
The toughening of the diglycidyl ether of bisphenol A epoxy resin with isocyanateterminated polyethers (ITPE) was investigated. The progress of the reaction and the structural changes during modification process wer... The toughening of the diglycidyl ether of bisphenol A epoxy resin with isocyanateterminated polyethers (ITPE) was investigated. The progress of the reaction and the structural changes during modification process were studied using FTIR spectroscopy. The studies support the proposition that TDI (tolylene diisocyanate) acts as a coupling agent between the epoxy and polyethers, forming a urethane linkage with the former and the latter, respectively. Me THPA-cured ER/ITPs blends were characterized using dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). It is indicated the glass transition temperature (T) of systems was lower than the T of pure epoxy resin and overfull ITPE separated from the modified epoxy resin and formed another phase at an ITPE-content of more than 10wt%. The thermal stability was decreased by the introduction of ITPE. The impact strength and the flexural strength of the cured modifiedepoxy increased with increasing the ITPE content and a maximum plateau value of about 24.03 kJ/m^2 and 130.56 MPa was measured in 10wt% ITPE. From scanning electron microscopy (SEM) studies of the fractrue surfaces of ER/ITPE systems, the nature of the micromechanisms responsible for the increases in toughness of the systems was identified. 展开更多
关键词 isocyanate-terminated polyethers epoxy resin DMA SEM impact strength
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SOLID-STATE VARIABLE-TEMPERATURE NMR STUDY ON THE PHASE SEPARATION OF POLYETHER POLYURETHANE ZWITTERIONOMERS
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作者 杨光 陈群 +2 位作者 王源身 杨昌正 邬学文 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第4期302-308,共7页
Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H... Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H NMR. It is found that upon ionization, degree ofphase separation in the polymer system decreased at first due to the loss of hard segmentregularity, while further ionization increased the degree of phase separation through increasinghard phase cohesion and difference of polarity between hard and soft segments. 展开更多
关键词 polyether polyurethane Variable temperature Wide-line NMR Phase separation
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IMMOBILIZATION OF POTENTIALLY BIOACTIVE MOIETIES ONTO POLYETHER WITH POLY(ETHYLENE GLYCOL)-SULFONATE SPACER
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作者 计剑 封麟先 +2 位作者 邱永兴 俞小洁 杨士林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第2期180-186,共7页
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-bifunc... 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. 展开更多
关键词 potentially bioactive moieties polyether biocompatible materials
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Synthesis of Arsamacrocyclic Polyethers
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作者 Xin You CHEN Guo Feng YU Wen Tian TAO (Department of Chemistry. Xiaogan Teachers College,Hubei 432100)(Department of Chemistry, Wuhan University,Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第8期665-666,共2页
The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR, H-1-NMR and MS.
关键词 macrocyclic compound arsamacrocyclic polyether SYNTHESIS
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THE COORDINATION BETWEEN SILVER NITRATE AND OPEN CHAIN POLYETHER
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作者 Li, Yongxiu Ni, Zhaoai Jiangxi University, Nanchang 330047, China Hangzhou University, Hangzhou 310028, China 《中国有色金属学会会刊:英文版》 CSCD 1993年第1期38-41,共4页
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 [Ag<sub>4</... 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 [Ag<sub>4</sub>L<sub>3</sub>](NO<sub>3</sub>)<sub>4</sub>. It is clear from the IR, UV and ’HNMR spectra that the ligand L coordinated to Ag<sup>+</sup> ion with its N and 0 atoms which connected with the terminal quinolyloxy group. 展开更多
关键词 OPEN CHAIN polyether SILVER NITRATE COORDINATION
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SYNTHESES OF POLYSTYRENE RESINS CONTAINING POLYETHER OLIGOMERS AND THEIR EXTRACTION FOR GOLD (Ⅲ)
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作者 董世华 刘石 徐羽梧 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第1期49-56,共8页
Three polystyrene resins containing polyether oligomers as extractants were synthesized andtheir extraction properties were studied. Gold (III) ion could be extracted rapidly by the resins(T_(1/2),<lmin. )with high... Three polystyrene resins containing polyether oligomers as extractants were synthesized andtheir extraction properties were studied. Gold (III) ion could be extracted rapidly by the resins(T_(1/2),<lmin. )with high efficiency and capacity (for LS-B resin that were 99. 8% and 95. 8mg/gRrespectively) from aqueous solution but most of the co-existing metal ions such as Pd (II),Cu(II), Zn (II), Pb (II) and Cd (II) were remained. The extraction capacity and strippingpercentage for gold (III) remained unchanged in four extraction-stripping cycles. The resins also showed good column extraction-elution properties. 展开更多
关键词 GOLD polyether oligomer Levextrel-type resin
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IONIC CONDUCTIVITY IN THE COMPLEXES OF COMB-SHAPED POLYETHER WITH LITHIUM AROMATIC SULFONATE
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作者 张升水 仇卫华 +1 位作者 薛大翠 刘庆国 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第3期267-272,共6页
Complexes of comb-shaped polyether and lithium aromatic sulfonates bearing different negative charge number were prepared by in situ thermal polymerization. Their conductivity depends deeply on salt content, ambient t... Complexes of comb-shaped polyether and lithium aromatic sulfonates bearing different negative charge number were prepared by in situ thermal polymerization. Their conductivity depends deeply on salt content, ambient temperature and negative charge number of the added salts. Results show that anions can be partly immobilized by increasing their negative charges at lower temperature. Against discharge time the short circuit current of the battery (Li/complex film/Li_x V_3O_8) is stabilized by increasing the anionic charge number of the complex. 展开更多
关键词 Polymeric solid electrolyte Ionic conductivity Comb-shaped polyether Lithium battery
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ION CONDUCTION IN COMPLEX OF ACRYLONITRILE-COPOLYMERIZED COMB POLYETHER WITH LITHIUM PERCHLORATE
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作者 许康 邓正华 万国祥 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第3期232-237,共6页
Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of... Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10^(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC. 展开更多
关键词 Comb polyether Complex with Li-salt Solid electrolyte Ion conductivity Structure and conductivity
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IONIC CONDUCTIVITIES OF SEGMENTED POLYETHER POLYURETHANEUREA COMPLEXES WITH LiClO_4
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作者 顾庆超 徐炜政 +1 位作者 叶温温 莫天麟 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第3期189-194,共6页
Ionic conductivity values for segmented polyether polyurethaneurea (PEUU) complexes with LiClO_4 were determined and values as high as~1.1×10^(-4) S·cm^(-1) at 353K and~1.0×10^(-5)S·cm^(-1) at 30... Ionic conductivity values for segmented polyether polyurethaneurea (PEUU) complexes with LiClO_4 were determined and values as high as~1.1×10^(-4) S·cm^(-1) at 353K and~1.0×10^(-5)S·cm^(-1) at 306K were achieved. The ionic conductivity data were analyzed using the VTF (Vogel-Tamman-Fulcher) equation and WLF (Williams-Landel-Ferry) type equation. Values have been estimated for the 'apparent' activation energies of ion transport from VTF equation and they lie in the range 2.70—5.53 kJ·mol^(-1). 展开更多
关键词 Segemented polyether polyurethaneureas Complex: Solid ionic conductor Ionic conductivity VTF (Vogel-Tamman-Fulcher) equation WLF equation
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Synthesis and Characterization of EO/PO Random Copolyethers
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作者 郭建国 苑仁旭 +3 位作者 何素芹 朱诚身 焦宇 江建明 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期60-64,共5页
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 potass... 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. 展开更多
关键词 ethylene oxide propylene oxide polyether propylene glycol
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