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Effects of Al(i-Bu)_3 on Propylene polymerization and Copolymerization by rac-Me_2.i(Ind)_2.rCl_2.MAO

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Chinese Chemical Letters 1998年第1期9卷 83-85页

作者： Zhi Qiang FAN yong Hui ZHANG Qi WANG Lin Xian FENG (department of {2. Science and engineering, zhejiang university, hangzhou 3.0027) zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

The effects of adding Al(i-C_4H_9)_3 (TBA) to rac-Me2.i(Ind)2.rCl2. MAO catalyzed propylene-1-octene copolymerization were studied. At TBA /MAO (Al/AI mole ratio) of about 0.6, the polymerization activity was found to be much higher than the system without TBA. Increases of polymer molecular weight and 1-octene content from addition of TBA were also observed.

关键词： propylene-1-octene polymerization metallocene catalyst

Synthesis, Purification and Characterization of Amphiphilic and Microphase Separated Graft Copolymer Polystyrene-g-Poly(ethylene oxide)

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Chemical Research in Chinese Universities 1992年第3期8卷 278-286页

作者： QIU yong-xing, YU Xiao-jie, FENG Lin-xian and YANG Shi-lin (department of {2. Science and engineering, zhejiang university, hangzhou)

The present paper covers the poly (ethylene oxide) macromer with vinyl benzyl terminal group (PEO-VB) prepared by deactivation of the alkoxide function of mono-functional 'living' PEO chains with vinyl benzyl chloride (VBC). The obtained macromers were subjected to careful purification and detailed characterization. A new kind of amphiphilic polystyrene-g-poly(ethylene oxide) (PS-g-PEO) with both mi-crophase separated and PEO side chains was synthesized from radical copolymerization of PEO-VB macromer with styrene monomer. An improved purification method, referred as 'selective dissolvation', was established for the isolation of graft copolymers from the grafting products, and the purity and yield of the purified copolymers were satisfactory. The well-defined structure of the purified copolymers was confirmed by IR, 1H NMR and GPC. The bulk composition of the graft copolymers was determined by a well-established first derivative UV spectrometry. Various experimental parameters controlling the copolymerization were also studied. The results indicate that the feed ratio of macromer to styrene (M/S) was the most important factor in determining the composition of the copolymers. Thus a series of PS-g-PEO with a wide range of bulk compositions were obtained simply by adjusting the value of M/S. As clearly indicated by transmission electron microscopy, this amphiphilic graft copolymers may readily form microphase separated structures.

关键词： Poly(ethyiene oxide) macromer Polystyrene-g-poly(ethylene oxide) Pu-rification of graft copolymer Amphiphilic and microphase separated structure Biocom-patible polymer

One-pot synthesis of a giant twisted double-layer chiral macrocycle via [4+8] imine condensation and its X-ray structure

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Chinese Chemical Letters 2024年第10期35卷 241-243页

作者： Yu Pang Min Wang Ning-Hua Yang Min Xue yong Yang School of Science Department of PhysicsKey Laboratory of Optical Field Manipulation of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018China School of Chemistry and Chemical engineering Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou310018China

Trifluoroacetic acid(TFA)catalyzed condensation reaction between tetraaminooxacalix[4]arene and N-alkylcarbazole-3,6-dicarbaldehyde in CH_(2.Cl2.fforded a single product in 87%–89%***-defined yet undissolvable1H NMR spectra suggested formation of robust and discrete structures in solution.X-ray single crystal analysis further revealed a giant twisted double-layer chiral macrocycle in the solid state,which was formed from[4+8]condensation of the two reactants via 16 imine *** calculations discovered that only the[4+8]twisted product is thermodynamically favorable,which accounts for its highly selective and efficient formation out of a library of many other combinations.

关键词： One-pot synthesis Oxacalixarene Dynamic covalent chemistry Chiral macrocycle X-ray single crystal

Advanced cellulose-based materials toward stabilizing zinc anodes

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Science china Chemistry 2024年第5期67卷 1465-1484页

作者： Zhijiang Li Xiang Chen Rui Zhang Taoyi shen Jianchao Sun Zhongce Hu Lin Li Lanlan Yang Hou-yong Yu College of Textile Science and engineering(International Institute of Silk) Zhejiang Sci-Tech UniversityHangzhou 310018China State Key Laboratory for Modification of Chemical Fibers and polymer Materials Donghua UniversityShanghai 201620China School of Environment and Material engineering Yantai UniversityYantai 264005China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Rechargeable aqueous zinc metal batteries(RAZMBs) have received extensive attention for large-scale energy storage systems due to the merits of Zn anodes, including moderate volumetric and gravimetric energy density, low redox potential, abundant reserve, low cost and impressive intrinsic safety. However, Zn anodes suffer from a series of adverse reactions(dendrite growth,hydrogen evolution, and surface passivation) resulting in low Coulombic efficiency, large polarization, and unsatisfied cycling performance, which inevitably hinder the wide application of RAZMBs. To address the above issues, cellulose-based materials are widely used for Zn anode protection because of their unique physical and chemical properties and other advantages such as biocompatibility, non-toxicity, degradability and easy extraction. In order to better understand the current progress in cellulosebased materials for the Zn anode protection, we have classified and summarized the relevant literatures. In this review, we summarize and elaborate the causes of poor reversibility for Zn anodes, including dendrite formation, hydrogen evolution, and surface passivation. Subsequently, the effective strategies(anode interfacial engineering, gel electrolyte optimization, and separator modification) of cellulose-based materials toward stabilizing Zn anodes are overviewed. In the end, the existing challenges and prospects of cellulose-based materials in Zn anode protection are summarized to shed light on future work.

关键词： Zn anode cellulose anode interfacial engineering gel electrolyte optimization separator modification

Improving Thermal-oxidative Aging Resistance of Styrene-butadiene Rubber by Antioxidant Loaded Silica Aerogel

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Chinese Journal of polymer Science 2024年第8期42卷 1198-1209页

作者： Xue-Fei Ping Yu Wang Lu Liu Fu-yong Liu Hong-Wei He Pi Wang Wen-Wen Yu Qiang Zheng College of Materials Science and engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical engineering Taiyuan 030032China Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

The antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine(4010NA)was dissolved in ethanol and impregnated into silica aerogel(SAG)via vacuum-pressure cycles,yielding composite particles(A-N)with enhanced sustained-release and reinforcing *** effect of A-N on the mechanical properties and thermal-oxidative aging resistance of styrene-butadiene rubber(SBR)vulcanizates was *** and BET assessments indicated that the loading efficiency of 4010NA in SAG reached 14.2.%within ethanol's solu bility *** A-N into SBR vulcanizates significantly elevated tensile strength by 17.5%and elongation at break by 41.9%over those with fumed silica and ***,A-N notably enhanced the thermal-oxidative aging resistance of *** aging for 96 h at 100℃,the tensile strength and elongation at break of SBR with A-N sustained 70.09%and 58.61%of their initial values,respectively,with the retention rate of elongation at break being 62.8%higher than that of SBR with fumed silica and free *** study revealed that A-N composite particles significantly inhibited the crosslinking in SBR's molecular chains,reducing hardening and embrittlement during later thermal-oxidative aging stages.

关键词： Styrene-butadiene rubber Silica aerogel Loading modification Thermal-oxidative aging

Synthesis of Long-Chain Oligomeric Donor and Acceptors via Direct Arylation for Organic Solar Cells

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Chinese Journal of Chemistry 2024年第5期42卷 523-532页

作者： Yu Wu Xin-Yu He Xu-Min Huang Ling-Jun Yang Peng Liu Na Chen Chang-Zhi Li Shi-yong Liu Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry College of MaterialsMetallurgical and ChemistryJiangxi University of Science and TechnologyGanzhouJiangxi341000 China department of polymer Science and {2. Zhejiang UniversityHangzhouZhejiang310027 China

The rapid synthesis of structurally complicated electron donors&acceptors still remains a major challenge in organic solar cells(OSC).In this work,we developed a highly efficient strategy to access long-chain oligomeric donor and acceptors for OSC applications.A series of cyclopentadithiophene(CPDT)and benzothiadiazole(BT)-basedπ-conjugated oligomers,i.e.,three oligomeric acceptors(BTDT)n-IC(n=1—3)and one long-chain oligomeric donor(BTDT)4-RD,are facilely synthesized by an atom-and step-economical,and labor-saving direct C—H arylation(DACH)reaction(i.e.,C—H/C—Br cross coupling).Note that(BTDT)4-RD involving five CPDT,four BT and two rhodamine(RD)building blocks is the longest oligomeric donor in the fullerene-free OSC devices ever *** dependence of the structure-property-performance correlation of(BTDT)n-IC(n=1—3)and(BTDT)4-RD on theπ-conjugation lengths is thoroughly investigated by opto-electrochemical measurements,bulk heterojunction(BHJ)OSC devices and ***(BTDT)1-IC:PBDB-T and(BTDT)4-RD:Y6 BHJs achieve power conversion efficiencies of 9.14%and 4.51%,*** findings demonstrate that DACH reaction is a powerful tool to tune the opto-electronic properties and device performances by regulating the lengths ofπ-conjugated oligomers with varied numbers of repeating units.

关键词： Long-chainπ-conjugated oligomer Organic solar cells Direct arylation Atom-economical synthesis Cyclopentadithiophene Benzothiadiazole C—H activation Conjugation Oligomers

Alkali Metal Ion Substituted Carboxymethyl Cellulose as Anode polymeric Binders for Rapidly Chargeable Lithium-Ion Batteries

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Energy & Environmental Materials 2024年第1期7卷 77-82页

作者： Seoungwoo Byun Zhu Liu Dong Ok Shin Kyuman Kim Jaecheol Choi Youngjoon Roh Dahee Jin Seungwon Jung Kyung-Geun Kim Young-Gi Lee Stefan Ringe yong Min Lee department of Energy Science and engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Korea ZJU-hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Intelligent Sensors Research Section Electronics and Telecommunications Research Institute(ETRI)Daejeon 34129Korea department of Advanced Device Technology University of Science and Technology(UST)Daejeon 34113Korea Intelligent polymer Research Institute and ARC Centre of Excellence for Electromaterials Science University of WollongongWollongong NSW 2522Australia department of Chemistry Korea UniversitySeoul 02841Korea Energy Science and engineering Research Center Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Korea

The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase ***,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)*** this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their *** lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for ***,Li-CMC cell with a capacity of 3 mAh cm^(-2.could be charged to>95%in 10 min,while a value above>85%was observed after 150 ***,the presented approach holds great promise for the realization of fast charging.

关键词： de-solvation digital twins fast charging graphite anodes polymeric binders

From oxygenated monomers to well-defined low-carbon polymers

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Chinese Chemical Letters 2024年第1期35卷 40-44页

作者： Yanni Xia Chengjian Zhang yong Wang Shunjie Liu Xinghong Zhang National Key Laboratory of Biobased Transportation Fuel Technology International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China School of Chemistry and Chemical engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shanxi-Zheda Institute of Advanced Materials and Chemical engineering Hangzhou 310027China

The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much *** minireview introduces the synthesis of a variety of degradable polymers from the(co)polymerizations of several typical oxygenated monomers such as epoxides,cyclic carbonates,cyclic esters,carbon dioxide(CO_(2.),carbonyl sulfide(COS),and cyclic *** highlight the catalysts and mechanisms for these(co)*** ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been *** also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center *** hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.

关键词： polymer synthesis Degradable polymer Low-carbon polymer Catalysis Ring-opening polymerization

New sustainable polymers with on-demand depolymerization property

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Science china Chemistry 2024年第9期67卷 2803-2841页

作者： Yangyang Sun Zesheng An Yanshan Gao Rongrong Hu Ye Liu Hua Lu Xiao-Bing Lu Xuan Pang Anjun Qin yong shen Youhua Tao Yu-Zhong Wang Junpeng Wang Gang Wu Guang-Peng Wu Tie-Qi Xu Xing-Hong Zhang Yuetao Zhang Zhenbiao Zhang Jian-Bo Zhu Miao Hong Zhibo Li State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China State Key Laboratory Base of Eco-Chemical engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou 510640China State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Collaborative Innovation Center for Eco-Friendly and Fire-Safety polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China School of polymer Science and polymer {2. the University of AkronAkronOH 44325USA MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State and Local Joint engineering Laboratory for Novel Functional polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

To combat the crisis of today's synthetic polymers arising from unsustainable production and disposal,it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable *** an emerging class of sustainable polymers,the development of chemically depolymerizable polymers(CDPs),which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers,offers an ideal solution to preserve finite natural resources,provides a feasible solution to the end-of-life issue of polymer waste,and thereby establishes a circular materials ***,two grand key challenges have been encountered in the establishment of practically useful CDPs:how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical ***,this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.

关键词： chemically depolymerizable polymers sustainable polymers depolymerization monomer recovery degradation plastics