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Synthesis and Magnetic Properties of Fe（Ⅱ） and Nd（Ⅲ） Complexes of Poly（N-2-thiazolylacrylamide）

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Chinese Chemical Letters 2005年第10期16卷 1413-1416页

作者： Ping ZHENG Wei Lin SUN zhi quan shen Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

N-2-Thiazolylacrylamide （NTA） was polymerized by a radical route to obtain the polymer in good yield. The polymer with a pendent heterocyclic group is soluble in common organic solvents, which allow to prepare the corresponding metal complexes with higher loads easily. FTIR, ^1H NMR, elemental analysis, and energy-dispersive X-Ray spectroscopy （EDX） were applied to characterize these materials. The magnetic behavior of Fe（Ⅱ） and Nd（Ⅲ） complexes of poly（N-2-thiazolylacrylamide） was examined by a PPMS-9T magnetometer, exhibiting the characteristics of a soft ferromagnet. It is found that the Nd（Ⅲ） complex has an extremely high relative saturation magnetization of 35 emu/g.

关键词： N-2-Thiazolylacrylamide polymer polymeric complex magnetic property synthesis.

Preparation of amphiphilic graft copolymer with polyisoprene backbone by combination of anionic polymerization and "click" reaction

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Chinese Chemical Letters 2012年第3期23卷 347-350页

作者： Fei Shao Xu Feng Ni zhi quan shen MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene＂click＂reaction and alcohol-isocyanate *** was synthesized by anionic polymerization using n-butyl lithium as initiator,and the pendant hydroxyl groups were introduced by the thiol-ene reaction of mercaptoethanol with the double bond of 1,2-addition units of PI backbone in the presence of radical initiator azobisisobutyronitrile. Isocyanate end group capped poly（ethylene glycol）（mPEG-NCO） was grafted onto the PI backbone through alcoholisocyanate reaction between the pendant hydroxyl groups and isocyanate group of *** structure of the graft copolymer were characterized and confirmed by means of size-exclusion chromatography,~1H NMR and FTIR spectroscopy.

关键词： Graft-copolymer Thiol-ene addition Isocyanate Click reaction

Polymerization of Methyl Methacrylate with Samarocene Complex Supported on Mesoporous Silica

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Chinese Chemical Letters 2001年第9期12卷 821-822页

作者： Xu Feng NI zhi quan shen Hajime YASUDA Institute of Polymer Science Zhejiang UniversityHangzhou 310027 Department of Applied Chemistry Faculty of EngineeringHiroshima UniversityHigashi-Hiroshima 724Japan

Samarocene complex was supported on a series of mesoporous silica with various pore sizes. Polymerization of methyl methacrylate (MMA) by these catalysts provide highly syndiotactic PMMAs with higher molecular weights... 详细信息

关键词： Mesoporous silica supported catalyst samarocene complex

Rare Earth Complex Initiated Ring-Opening Polymerization of 2,2-Dimethyltrimethylene Carbonate

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Chinese Chemical Letters 2001年第1期12卷 41-42页

作者： Jun LING Yi Feng ZHANG zhi quan shen Institute of Polymer Science Zhejiang UniversityHangzhou 310027

The ring opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) initiated by single component of tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanide (Ln(OAr)(3)) is reported. The initiators are highly active to the polymerization and give high molecular weight polymers. (HNMR)-H-1 spectra and DSC measurement suggest the polymerization is free of decarboxylation. Mechanism study shows that the monomer insertion is via the break of acyl-oxygen bond of DTC.

关键词： tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanide 2,2-dimethyltrimethylene carbonate ring-opening polymerization

SYNTHESIS AND MAGNETIC PROPERTIES OF COMPLEXES OF A CONJUGATED HYPERBRANCHED POLYMER CONTAINING BITHIAZOLE RINGS

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Chinese Journal of Polymer Science 2012年第5期30卷 759-769页

作者： Neng-wen Ding 孙维林 Yan Lin zhi-quan shen Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou310027China Ningbo City College of Vocational Technology Ninbo315100China

A novel conjugated hyperbranched polymer containing bithiazole rings （PBTADB） was synthesized by polycondensation of 1,3,5-benzenetricarboxaldehyde and 2,2＇-diamino-4,4＇-bithiazole （DABT）. The structure of the hyperbranched polymer was confirmed by FT-IR and 1H-NMR. PBTADB dissolved in organic polar solvents such as DMSO and NMP. Bithiazole tings were introduced to provide bidentate N-donor sites for binding metal ions. The metal complexes were prepared by chelation of the polymer with Co2＋ and Sm3＋. The magnetic behavior of coolcdination compounds was measured as a function of magnetic field strength （0-4.8 ×106 A/m） at 5 K and as a fimetion of temperature （5-300 K） at magnetic field strength of 2.4×106 A/re. The magnetic hysteresis loops of PBTADB-Sm3＋ and PBTADB-Co2＋ showed the typical ＇S＇ shape at 5 K with the Curie-Weiss temperature To = 96 K and 41 K respectively. The results show that they exhibit properties of soft ferromagnetic materials.

关键词： Bithiazole Conjugated hyperbranched polymer Magnetic properties.

Mechanism of Janus Polymerization: A DFT StudyFig. S3 Energy profiles of anionic polymerization in Stage I under B3LYP/6-31G(d,p)(blue) and B3LYP/aug-cc-p VTZ//B3LYP/6-31G(d,p)(red). Scheme S1. Propagation process of CL/THF on cationic side in Stage I of J

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Chinese Journal of Polymer Science 2019年第10期37卷 990-994,I0004页

作者： Tian-Wen Bai Xu-Feng Ni Jun Ling zhi-quan shen Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

Janus polymerization is featured as a combination of cationic and anionic growing ends in one living polymer chain. In the copolymerization of THF and CL catalyzed by lutetium triflates and initiated by propylene oxide, three stages are identified by kinetic study including(1) fast cationic polymerization with slow anionic one,(2) fast anionic polymerization with dormant cationic one, and(3)reactivation of cationic polymerization with coupling of anionic and cationic chain ends. In this work, density functional theory(DFT)calculation is employed to investigate the reaction details of ionic polymerization and dormancy. A “tripedal crow” configuration is proposed to illustrate the unique high-coordinated ligand exchange configuration in anionic polymerization in different stages. The trigger of dormancy is determined as chain structures rather than concentration of triflate anion according to both calculation and experimental results.

关键词： Rare earth metal catalysts Ring-opening polymerization Ionic polymerization Reaction mechanism quantum chemicalcomputation

Synthesis of α-Hydroxy-ω-Aminotelechelic Polypeptide from α-Amino Acid N-Carboxyanhydrides Catalyzed by Alkali-metal Borohydrides

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Chinese Journal of Polymer Science 2014年第6期32卷 743-750页

作者： Hui Peng Wan-li Chen Jie Kong zhi-quan shen 凌君 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Center of Analysis & Measurement Zhejiang University of Technology Shaanxi Key Laboratory of Macromolecular Science and Technology School of Science Northwestern Polytechnical University

It is reported that alkali-metal borohydrides （MBH4, M = Li, Na and K） are efficient catalysts for ring opening polymerization （ROP） of α-amino acid N-carboxyanhydrides （NCAs）. Polypeptides are prepared in quantitative yields with relatively narrow molecular weight distributions （MWDs = 1.1-1.5） which depend on the reaction temperature. End groups of the produced polypeptide are studied in detail by MALDI-ToF MS, IH-NMR, 13C-NMR, IH-1H COSY and IH-13C HMQC analyses. The results indicate that α-hydroxy-ω-aminotelechelic polypeptides are formed which are suitable for post- polymerization functionalization.

关键词： Polypeptide Alkali-metal borohydride α -Amino acid N-carboxyanhydride End group functionalization.

Synthesis and characterization of biodegradable amphiphilic PEG-grafted poly(DTC-co-CL)

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Chinese Chemical Letters 2010年第10期21卷 1255-1258页

作者： Qiu Jin Zhang Wei Pu Zhu zhi quan shen MOE Key Laboratory of Macromolecule Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

A novel biodegradable copolymer, poly（5,5-dibromomethyltrimethylene carbonate-co-ε-caprolactone）（poly（DBTC-co-CL）） with pendant bromine groups, was synthesized via ring-opening polymerization （ROP） of ε-caprolactone （CL） and 5,5- dibromomethyltrimethylene carbonate （DBTC） using stannous octoate （Sn（Oct）2） as catalyst. Then the pendant bromine groups were completely converted into azide form, which permitted ＂click＂ reaction with alkyne-terminated polyethylene （A-PEG） by Huisgen 1,3-dipolar cycloadditions preparing biodegradable amphiphilic poly（DTC-co-CL）-g-PEG graft copolymer. The graft copolymer was characterized by nuclear magnetic resonance （NMR） and size-exclusion chromatography （SEC）.

关键词： Polycarbonate "Click" reaction Graft copolymer Ring-opening polymerization

Copolymerization of Styrene with N-phenylmaleimide by Rare Earth Coordination Catalysts

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Chinese Chemical Letters 2002年第7期13卷 685-686页

作者： Yan Bing LU Wei Lin SUN zhi quan shen Institute of Polymer Science Zhejiang UniversityHangzhou 310027

Copolymerization of styrene (St) with N-phenylmaleimide (NPMI) was studied with rare earth coordination catalyst Nd(naph)3-AlEt3 in toluene. Characterization of the copolymers showed that the copolymers possess an al... 详细信息

关键词： Copolymerization styrene N-phenylmaleimide rare earth coordination catalyst.