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| 1 | Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent显示文摘Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3 to 27.4 kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241 μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent. | LI Xiaobin1,2, CAO Hongbin1 & ZHANG Yi1 1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China | 2006 | Science China Chemistry2006，49，4： | 6 |
| 2 | Synthesis of waterborne polyurethane using snow as dispersant:Structures and properties controlled by polyols utilization显示文摘waterborne polyurethane (WPU) dispersions have gained attention towards environm entally-friendly synthesis. In this article, a series of waterborne polyurethane em ulsions was successfully synthesized and extensively characterized in terms of thermal, mechanical properties, hydrophilic behavior and morphology. Snowwas chosen as dispersant instead of comm only used water. Preparation param eters such as intrinsic properties and molecular weight of polyols were discussed systematically. A chain structure was confirmed by Fourier transform infrared (FT-IR) spectroscopy. when com paring the nature of the polyols (PPG, PEG and PNA, 2000g/mol) of this study, as-synthesized polyether waterborne polyurethane provided higher solid content, viscosity and water-resistance. However, polyester waterborne polyurethane perform ed differently and it exhibited higher therm al stability and crystallinity. When com paring the samples (WPU-N210, WPU-N220, WPU-N230 and WPU-N240) with different molecular weight of the same polyol (PPG) used as soft segment, the emulsion WPU-N220 with molecular weight of 2000g/mol PPG provided the highest solid content and lowest viscosity. It was observed th at particle size was uniform and highly dispersed for all sam ples from TEM images. Therm ogravim etric, differential scanning calorim etry (DSC) and X-ray diffraction results dem onstrated that the emulsion WPU-N230 with m olecular weight of 3000 g/mol PPG possessed higher therm al stability and crystallinity than the other samples. The reason was that the Tg and thermal stability were increased with increasing molecular weight. when molecular weight increased, the arrangem ent of soft segm ent became more regular and so did the regularity of the molecular chains. This work demonstrated that different polyols as soft segment applied could lead to great differences in the structure and property of the resulting WPU. | Changqing Fang Shaofei Pan Zhen Wang Xing Zhou Wanqing Lei Youliang Cheng | 2019 | Journal of Materials Science & Technology2019，35，7： | 4 |
| 3 | Synthesis and magnetic resonance of new heteropolynuclear Ln(III)-Cu(II) complexes with noncyclic polyether Schiff base显示文摘A series of novel heteropolynuclear complexes of Ln(III)\|Cu(II) and Cu(II) complex with noncyclic polyether Schiff base, salicylidene diethylene glycol diamine (SALDA), have been synthesized for the first time. The isolated complexes are formulated as [LnCu\-2(SALDA)\-3(NO\-3)\-5](NO\-3)\-2·4H\-2O (Ln=La, Pr, Nd, Sm, Gd, Tb, Er, Yb, Y) and [Cu(SALDA)(NO\-3)](NO\-3)·H\-2O. Synthesis methods are reported herein. The differences in their compositions, structures and coordination have been investigated by UV, IR, magnetic susceptibility, especially by 1 H and 13 C NMR spectra. It has been found that ν (CN) in the Ln(III)\|Cu(II) complexes are split up into two peaks with a far distance and it may be used as a probe for distinguishing them from others. In addition, it is suggested that the ethereal oxygen donors are not all coordinated. The good catalysis effect for the polymerization of methyl methacrylate (MMA) are reported for the first time. The results show that the catalytic activity of Nd\|Cu\|SALDA complex is better than that of the others and its syndiotactic sequence is ~72% as well, the conversion increases to 88%. | 姚克敏 吴静 沈联芳 袁汉珍 | 1998 | Science China Chemistry1998，41，4： | 1 |
| 4 | Accelerated Approach to the Synthesis of Fluoriated Polyether Dendrimers显示文摘Fluorinated polyether dendritic sectors 4, 7 and 10 from the first to the thirdgenerations, respectively, were prepared by a convergent approach from readily availablepentafluorophenol, phloroglucinol and 1,3-dibromopropane. These dendritic sectors have goodsolubility properties and are stable in both acidic and basic media. Hence they are useful dendriticbuilding blocks for the preparation of functional dendrimers. | Cao, XP Li, XH Chow, HF Li, Y | 1998 | Chinese Chemical Letters1998，9，9： | 1 |
| 5 | Synthesis of Arsamacrocyclic Polyethers显示文摘The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR 1H-NMR and MS. | Xin You CHEN Guo Feng YU Wen Tian TAO (Department of Chemistry. Xiaogan Teachers College,Hubei 432100)(Department of Chemistry, Wuhan University,Wuhan 430072) | 1999 | Chinese Chemical Letters1999，10，8： | 0 |
| 6 | Study on EPR Spectra of Three Gadolinium Complexes With Noncyclic Polyether Schiff Bases显示文摘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. | 陈德余 姚克敏 封子先 蔡乐真 周佩芬 薛祺 | 1994 | Science China Chemistry1994，37，2： | 0 |
| 7 | IONIC CONDUCTIVITIES OF SEGMENTED POLYETHER POLYURETHANEUREA COMPLEXES WITH LiClO_4显示文摘Ionic conductivity values for segmented polyether polyurethaneurea (PEUU) complexes with LiClO4 were determined and values as high as~1.1×10-4 S·cm-1 at 353K and~1.0×10-5S·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. | 顾庆超 徐炜政 叶温温 莫天麟 | 1991 | Chinese Journal of Polymer Science1991，9，3： | 0 |
| 8 | ION CONDUCTION IN COMPLEX OF ACRYLONITRILE-COPOLYMERIZED COMB POLYETHER WITH LITHIUM PERCHLORATE显示文摘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 7.0×10-5S/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 Tg and by the study of TSC. | 许康 邓正华 万国祥 | 1991 | Chinese Journal of Polymer Science1991，9，3： | 0 |
| 9 | THE COORDINATION BETWEEN SILVER NITRATE AND OPEN CHAIN POLYETHER显示文摘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. | Li, Yongxiu Ni, Zhaoai Jiangxi University, Nanchang 330047, China Hangzhou University, Hangzhou 310028, China | 1993 | 中国有色金属学会会刊:英文版1993，3，1： | 0 |
| 10 | Rare earth complexes with noncyclic polyether-methionine Schiff base显示文摘A novel Schiff base (TAMET) was synthesized by the condensation of tetraglycol aldehyde with methionine and a mild oxidant CrO3· (C5H5N)2 was selected for the reaction. Seven new rare earth complexes with this Schiff base have been synthesized and characterized by elemental analysis, TG-DTA, molar conductivity, magnetic susceptibility and IR, especially 1H NMR spectra. Information was obtained from reflectance spectra and the coordination of sulfur atom to rare earths was discussed. The experimental results show that thesecompounds have some biological activity and could dispose of O2. | 姚克敏 鲁桂 沈联芳 | 1999 | Chinese Journal of Chemistry1999，17，6： | 0 |
| 11 | Enhanced Pervaporative Separation of Thiophene/n-Heptane Using Metal Loaded PEBAX/PAN Membranes显示文摘The mass transfer of thiophene through pervaporation(PV)membranes could be facilitated by certain transitional metal ions like Ag^+,Mn^2+,and Cr^3+thanks to their p complexation with thiophene.In this study,Ag^+,Mn^2+,and Cr^3+ions were loaded onto the polyether block amide(PEBAX)/PAN composite membranes and were tested on the performance for separation of thiophene/n-heptane mixture.Pervaporation test results showed that the pervaporative separation index increased significantly to 73.1%,75.5%,and 97.2%at 30℃for the Ag^+-,Mn2^+-,Cr3^+-loaded PEBAX membranes,respectively,as compared to the pristine PEBAX/PAN composite membrane. | Han Jianjian Wang Yidong Hu Yongjie Liu Kun Muhammad Yaseen Hu Minzhuan | 2019 | China Petroleum Processing & Petrochemical Technology2019，21，3： | 0 |
| 12 | SOLID-STATE VARIABLE-TEMPERATURE NMR STUDY ON THE PHASE SEPARATION OF POLYETHER POLYURETHANE ZWITTERIONOMERS显示文摘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. | 杨光 陈群 王源身 杨昌正 邬学文 | 1994 | Chinese Journal of Polymer Science1994，12，4： | 0 |
| 13 | Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides显示文摘Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic systems.The new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability. | Feng Ren Zhuang-Zhuang Liang Ming-Xin Niu Chen-Yang Hu Xuan Pang | 2024 | Chinese Journal of Polymer Science2024，42，2： | 0 |
| 14 | IMMOBILIZATION OF POTENTIALLY BIOACTIVE MOIETIES ONTO POLYETHER WITH POLY(ETHYLENE GLYCOL)-SULFONATE SPACER显示文摘A new reactive graft copolymer, poly(tetramthylene glycol) - graft-w-propyl sodiumsulfonate-poly(ethylene glycol) (PTMG-g-PEG-CH2CH2CH2SO3-Na+), was synthesizedby the cationic polymerization of a-w-bifunctional PEG macromonomer (O?CH2—PEG——CH2 CH2 CH2 SO3 Na) and THF. The obtained copolymer exhibits the expected structureas 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 sulfonylchloride. So the new reactive graft copolymer (PTMG-g-PEG-CH2CH2CH2SO3-Na+) isexpected to be very useful in attachment of potentially bioactive moieties to polymer viaa hydrophilic PEG spacer. | 计剑 封麟先 邱永兴 俞小洁 杨士林 | 1997 | Chinese Journal of Polymer Science1997，15，2： | 0 |
| 15 | SURFACE MODIFICATION OF CaCO_3 WITH DENDRITIC CARBOXYLIC ACIDS显示文摘Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at the focal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO3 and the dendritic modifier was proven by IR and mass spectroscopy of the modified CaCO3 after thorough extraction with dichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount of bonded molecules decreased with increasing generation number due to the larger number of branches. Compared to unmodified CaCO3, the modified CaCO3 possess different dispersibility in water and in organic solvents. | Zhao-xia Guo Jian Yu Institute of Polymer Science and Engineering Department of Chemical Engineering Tsinghua University Beijing 100084 China | 2002 | Chinese Journal of Polymer Science2002，20，3： | 0 |
| 16 | SYNTHESES OF POLYSTYRENE RESINS CONTAINING POLYETHER OLIGOMERS AND THEIR EXTRACTION FOR GOLD (Ⅲ)显示文摘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(T1/2,<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. | 董世华 刘石 徐羽梧 | 1994 | Chinese Journal of Polymer Science1994，12，1： | 0 |
| 17 | Upcycling Polytetrahydrofuran to Polyester显示文摘One major remaining challenge in polymer chemistry is the development of efficient chemical recycling strategies to fully retrieve starting materials.Polytetrahydrofuran(PTHF)is widely used,but its stable ether bonds make it difficult to chemically reuse after disposal.Here,we propose a“polymer A→polymer B”strategy for one-step quantitative upcycling of PTHF to polyesters.The route undergoes a cascade process:PTHF is depolymerized to give tetrahydrofuran(THF)that then alternately copolymerizes with cyclic anhydrides in situ,thereby pushing the chemical equilibrium of“PTHF⇌THF”to the right.The protocol demonstrates facile features:the use of common and metal-free Brønsted/Lewis acid as catalyst,a favorable reaction temperature of 100℃,and no use of solvents.This method also accommodates 18 cyclic anhydrides to give a library of polyesters with alternating sequences,tunable thermal properties,and high-fidelity carboxyl terminals.This is an unprecedented strategy for chemical recycling of waste polyether. | Xun Zhang Yue Sun Chengjian Zhang Xinghong Zhang | 2023 | CCS Chemistry2023，5，5： | 0 |
| 18 | IONIC CONDUCTIVITY IN THE COMPLEXES OF COMB-SHAPED POLYETHER WITH LITHIUM AROMATIC SULFONATE显示文摘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/Lix V3O8) is stabilized by increasing the anionic charge number of the complex. | 张升水 仇卫华 薛大翠 刘庆国 | 1993 | Chinese Journal of Polymer Science1993，11，3： | 0 |
| 19 | Structure dependence of intramolecular photoinduced electron transfer in 9-aminoacridine benzoyl esters dyads linked by a polyether chain显示文摘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 energy.This 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 | Li, SL Tian, HJ Zhou, QF Li, ZH Xu, HJ | 1997 | Chinese Science Bulletin1997，42，19： | 0 |
| 20 | Migration of Cations and Anions in Amorphous Polymer Electrolytes显示文摘1 Results Polymer electrolytes are used as ion conductors in batteries and fuel cells.Simple systems consist of a polymer matrix complexing an inorganic salt and are fully amorphous at the temperatures of interest.Both cations and anions are mobile and contribute to charge transport.Most studies on polymer electrolytes use the electrical conductivity to characterize the ion mobility.However,conductivity measurements cannot discriminate between cations and anions.This paper reports some recent results fr... | N.A.Stolwijk S.H.Obeidi M.Wiencierz | 2007 | 复旦学报(自然科学版)2007，46，5： | 0 |
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