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Chinese Journal of Polymer Science 2014年第3期32卷 333-349页

作者： Lu Wang zhi-wei Jiang Feng Liu zhi-jie zhang 唐涛 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

Effects of branches on the crystallization kinetics of polypropylene-g-polystyrene （PP-g-PS） and polypropylene-g- poly（n-butyl acrylate）（PP-g-PnBA） graft copolymers with well-defined molecular structures were systematically investigated by DSC. The Avrami equation was used to analyze the isothermal crystallization process, while the analysis of nonisothermal crystallization process was based on the Jeziorny-modified Avrami model and Mo model. The kinetics results of isothermal and nonisothermal crystallization verified the peculiar effects of branches on the crystallization process of PP backbones in PP-g-PS and PP-g-PnBA graft copolymers： on one hand, the interaction between branches （n-n interaction between PS branches, or dipole-dipole interaction between PnBA branches） restrained the mobility and reptation ability of the PP backbones, which hindered the crystallization process; on the other hand, the heterogeneous nucleation effect resulting from the branched structure and fluctuation-assisted nucleation mechanism （caused by microphase separation between the PS or PnBA rich phase and the PP rich phase） became more pronounced with increasing branch length, which facilitated the crystallization process.

关键词： Polypropylene Polypropylene-g-polystyrene graft copolymer Polypropylene-g-poly(n-butyl acrylate) graftcopolymer Isothermal crystallization Nonisothermal crystallization.

Synthesis of Star-like Polybutadienes by a Combination of Living Anionic Polymerization and “Click” Coupling Method

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Chinese Journal of Polymer Science 2014年第6期32卷 731-742页

作者： Guang-chun zhang Jun Zheng Feng Liu zhi-jie zhang 马丽唐涛 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

Three-arm and four-arm star-like polybutadienes （PBds） were synthesized via the combination of living anionic polymerization and the click coupling method. Kinetic study showed that the click reaction between the azido group terminated PBd-t-N3 and the alkyne-containing multifunctional linking reagent was fast and highly efficient. All coupling reactions were fully accomplished within 40 min at 50 ℃ in toluene in the presence of the reducing agent Cu（0）, proven by 1H-NMR, FTIR and GPC measurements. For the coupling reactions between the PBd-t-N3 polymer and dialkyne-containing compound, the final conversion of the coupled PBd-PBd polymer was ca. 97.0%. When a PBd-t-N3 polymer was reacted with trialkyne-containing or tetraalkyne-containing compound, the conversion of three-arm or four-arm PBd was around 95.5% or 87.0%, respectively. Several factors influencing the coupling efficiency were studied, including the molecular weight of the initial PBd-t-N3, arm numbers and the molar ratio of the azido group to the alkynyl group. The results indicated that the conversion of the target products would be promoted when the molecular weight of the PBd-t-N3 was low and the molar ratio of the azido to alkynyl groups was close to 1.

关键词： Polybutadiene Living anionic polymerization Click chemistry Kinetic study Coupling efficiency Star-like.

Random Binary Brush Architecture Enhances both Ionic Conductivity and Mechanical Strength at Room Temperature

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Chinese Journal of Polymer Science 2018年第1期36卷 78-84页

作者： Yu-Feng Lyu zhi-jie zhang Chang Liu zhi Geng Long-Cheng Gao Quan Chen Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry and EnvironmentBeihangUniversityBeijing 100191China State KeyLaboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.

关键词： Binary brush copolymer PEO Ionic conductivity Phase separation

Silazyl-Lithiums: A kind of new Initiators for the Anionic Non- equilibrium Ring-opening Polymerization of Octamethylcyclotetrasiloxane (D_4)

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Chinese Chemical Letters 2002年第12期13卷 1174-1177页

作者： Shun Xing SU zhi jie zhang zhi Min ZHENG Ze Min XIE State Key Laboratory of Engineering Plastics Center for Molecular ScienceInstitute of Chemistrythe Chinese Academy of SciencesBeijing 100080

The initiation reactions in the anionic non-equilibrium polymerization of octamethy- lcyclotetrasiloxane (D4) initiated by silazyllithiums were investigated. It was found that the structure of the substituents on the... 详细信息

关键词： Anionic non-equilibrium polymerization polysiloxane silazyl-lithiums.

Synthesis of Some New Derivatives of 1,3-Dichloro-1,1,3,3-tetraphenyldisilazane

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Chinese Chemical Letters 2001年第1期12卷 35-38页

作者： Cai Hong XU zhi jie zhang Yong Min LI zhi Min ZHENG Ze Min XIE Center for Molecular Science Institute of ChemistryThe Chinese Academy of SciencesBeijing 100080

The reactive properties of 1,3-dichloro-1,1,3,3-tetraphenyldisilazane (DCTPS) with water, methanol, phenylamine and lithium salt of hexamethylcyclotrisilazane (D-3(NLi)) were investigated, and four new derivatives wer... 详细信息

关键词： 1,3-dichloro-1,1,3,3-tetraphenyldisilazane derivatives reactive properties

Preparation of Dendritic Carbosilane-supported Palladium Catalyst and Its Catalytic Activity in Hydrogenation of Organic Compounds

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Chinese Chemical Letters 2005年第10期16卷 1389-1392页

作者： Chun Fang LI Dong Xiang LI zhi jie zhang Sheng Yu FENG School of Chemistry and Chemical Engineering Shandong University Jinan 250100 School of Chemistry Chemical Engineering and Materials Shandong Normal University Jinan 250014 Institute of Chemistry Chinese Academy of Sciences Beijing 100080

The preparation of palladium complex from PdCl2·2H2O and carbosilane dendrimers with pelripheral aminopropyl groups was described. The compound obtained was characterized by IR, H NMR, X-ray photoelectron spectroscopy （XPS） and inductively coupled plasma atomic emission spectrometric （ICP-AES） spectroscopy respectively. The metal complex was employed as catalyst in hydrogenation of organic compounds. The high activity of the complex was probably due to the formation of the coordinatively unsaturated palladium.

关键词： Dendrimer complex catalysis.

New synthesis of bis(disiloxanyl)-m-carboranes

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Chinese Chemical Letters 2012年第6期23卷 650-652页

作者： Xue Chao zhang Ling Hong Kong Hong jie Sun Yong Xia Tan Li Na Dai Xue Zhong zhang zhi jie zhang Ze Min Xie Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China College of Chemistry and Chemical Engineering Graduate University of Chinese Acatemy of Sciences Beijing 100049 China

Four bis（disiloxanyl）-m-carboranes （（RSiMe2OSiMe2）2-m-C2BloHlo, R = H, vinyl, ethynyl, aUyl） were synthesized from the reaction of bis（hydroxydimethylsilyl）-m-carborane and disilazanes, and characterized by in... 详细信息

关键词： Bis(disiloxanyl)-m-carborane Silazane Condensation Siloxane

Formation and Structural Evolution of Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 Nanocrystalline Alloy

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 313-318页

作者： Yao-Xiang Geng Hong-Yu Ding Dong-Peng Wang zhi-jie zhang Hong-Bo Ju Li-Hua Yu Jun-Hua Xu School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Marine Equipment and Technology Institute Jiangsu University of Science and TechnologyZhenjiang 212003China

A 2.5-mm Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 glassy rod was successfully fabricated using copper mold *** introduction of Cu resulted in the formation of large quantities of a-Fe nanoparticles embedded in the glassy matrix after isothermal *** Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 nanocrystalline alloy exhibited high saturation magnetization(~1.26 T) and a low coercive force(~0.8 A/m) after annealing at 833 K for 15 min due to the precipitation of ~15-nm-sized a-Fe nanoparticles in the glassy *** structural evolution of the FeBSiNbZrCu amorphous alloy during the annealing process was discussed using a dual-cluster model.

关键词： Nanocrystalline alloy Magnetic property Dual-cluster model Structural evolution

Recent advances in Fe-N-C-and Co-N-C-based materials as bifunctional electrocatalysts for oxygen reduction and oxygen evolution

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Science China Chemistry 2024年第4期67卷 1137-1160页

作者： Hui-Min Xu Hong-Rui Zhu Chen-Jin Huang zhi-jie zhang Ting-Yu Shuai Qi-Ni Zhan Gao-Ren Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts

Double active sites promoting hydrogen evolution activity and stability of CoRuOH/Co_(2)P by rapid hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 206-211页

作者： Bin Dong Ning Yu Qiu-Yue Wang Jing-Ke Ren Xin-Yu zhang zhi-jie zhang Ruo-Yao Fan Da-Peng Liu Yong-Ming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Cobalt-based phosphides show excellent hydrogen evolution reaction(HER)performance,however,improving the intrinsic activity and stability of it in alkaline electrolyte still remains a ***,CoRuOH/Co_(2)P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis(30 s).The OH-from rapid surface hydrolysis of Co_(2)P as a hydrogen adsorption site can facilitate the formation of thin CoRuOH layer as a water dissociation site,which may bring out better synergistic effect for alkaline ***,the covering of CoRuOH can improve the stability of Co_(2)P for *** drives at 100 mA/cm^(2),it only requires overpotential of 81 mV in 1.0 mol/L KOH(25℃).Even at higher current density(1000 mA/cm^(2)),CoRuOH/Co_(2)P/CF can also operate stability for at least 100 *** coupling with NiFe-LDH/IF in a two-electrode system,the voltage of NiFe-LDH/IF(+)||CoRuOH/Co_(2)P/CF(-)at 1000 mA/cm^(2)is merely 1.77 V with 100 h,demonstrating great potential for water *** implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.

关键词： CoRuOH/Co_(2)P/CF Enhanced activity and stability Double active site Large current density Hydrogen evolution reaction