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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang Ming-Xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

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.

关键词： Polyester polyether Alternative copolymer Ring-opening polymerization

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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.

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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

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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.

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Synthesis and magnetic resonance of new heteropolynuclear Ln(III)-Cu(II) complexes with noncyclic polyether Schiff base

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Science China Chemistry 1998年第4期41卷 371-376页

作者：姚克敏吴静沈联芳袁汉珍 Department of Chemistry Zhejiang University Hangzhou China Department of Chemistry Hangzhou Teachers’ College Hangzhou China Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics & Mathematics Chinese Academy of Sciences Wuhan China

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%.

关键词： lanthanide noncyclic polyether Schiff base heteropolynuclear complex NMR spectra.

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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 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

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

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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

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Upcycling Polytetrahydrofuran to Polyester

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CCS Chemistry 2023年第5期5卷 1233-1241页

作者： Xun Zhang Yue Sun Chengjian Zhang Xinghong Zhang State Key Laboratory of Motor Vehicle Biofuel Technology International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027

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.

关键词： upcycling polymer chemically reuse polyester polyether polytetrahydrofuran

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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 foam.The fillers with the particle sizes of 50μm each were mixed in the ratio of 50:50.Diverse 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 produced.The unfilled foam(0%filler)served as the standard control sample.The 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 foam.The 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 thicker.Eggshell and groundnut husk fillers may be used in the making of flexible polyether foam since these materials are organic in natures.They can improve the mechanical properties and biodegradability of polyurethane product.The 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

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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)

ＥＮＨＡＮＣＥＭＥＮＴＯＦＥＮＥＲＧＹＴＲＡＮＳＦＥＲＦＲＯＭＴＨＥＴＥＲＭＩＮＡＬＣＨＲＯＭＯＰＨＯＲＥＯＦＰＯＬＹＥＴＨＥＲＴＯＥＵＲＯＰＩＵＭＣＡＴＩＯＮ（Ⅲ）ＶＩＡＣＯＭＰＬＥＸＡＴＩＯＮＥＮＨＡＮＣＥＭＥＮ... 详细信息

ＥＮＨＡＮＣＥＭＥＮＴＯＦＥＮＥＲＧＹＴＲＡＮＳＦＥＲＦＲＯＭＴＨＥＴＥＲＭＩＮＡＬＣＨＲＯＭＯＰＨＯＲＥＯＦＰＯＬＹＥＴＨＥＲＴＯＥＵＲＯＰＩＵＭＣＡＴＩＯＮ（Ⅲ）ＶＩＡＣＯＭＰＬＥＸＡＴＩＯＮＥＮＨＡＮＣＥＭＥＮＴＯＦＥＮＥＲＧＹＴＲＡＮＳＦＥＲ...

关键词： complexation polyether europium energy transfer

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