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Chinese Journal of Chemistry 2022年第21期40卷 2516-2524页

作者： Chunping Feng Debao Mu Xuehua Zhu Yaorong Wang Dan Yuan Yingming Yao Key Laboratory of Organic Synthesis of Jiangsu Province State and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering&Materials ScienceDushu Lake CampusSoochow UniversitySuzhouJiangsu215123China School of Chemistry and Life Science Suzhou University of Science and TechnologySuzhouJiangsu 215009China

The reactivities of benzoxazine functionalized amine bridged bis(phenol)s LnH_(2)(n=1—3)with rare earth metal complexes were explored,founding that both the aryl substituents of the ligand and the rare earth metals h... 详细信息

关键词： Rare earth metal complex Bridging ligands rac-LA ring opening polymerization Heteroselectivity

Recent Advances in the Synthesis and polymerization of New CO_(2)-Based Cyclic

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Chinese Journal of Chemistry 2024年第4期42卷 430-443页

作者： Matteo Lanzi Arjan W.Kleij Institute of Chemical Research of Catalonia(ICIQ) The Barcelona Institute of Science and Technology(BIST)Av.Països Catalans 1643007 TarragonaSpain Catalan Institute of Research and Advanced Studies(ICREA) Pg.Lluís Companys 2308010 BarcelonaSpain

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering polymers.This minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based synthons.In addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate monomers.Future perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

关键词： Carbon dioxide Cyclic carbonates Functional macromolecules Heterocycles Polycarbonates Recycling ring opening polymerization

ring opening polymerization OF TETRAHYDROFURAN CATALYSED BY MAGHNITE-H^+

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Chinese Journal of Polymer Science 2012年第1期30卷 56-62页

作者： Khadidja Benkenfoud Amine Harrane Mohammed Belbachir Laboratoire de Chimie des Polymeres Departement de Chimie Faculte des SciencesUniversite d'Oran Es-SeniaBP No 1524 El M'Naouar31000 OranAlgeria

The cationic ring-opening polymerization of tetrahydrofiiran using maghnite-H~＋ is reported.Maghnite-H~＋,is a non-toxic solid catalyst issued from proton exchanged montmorillonite clay.Polytetrahydrofuran,also called ＂poly（butandiol） ether＂,with acetate and hydroxyl end groups was successfully synthesized.Effects of reaction temperature, weight ratio of initiator/monomer and reaction time on the conversion of monomer and on the molecular weight are investigated.A cationic mechanism of the reaction was proposed.This chemistry can be considered as a suitable route for preparing poly（THF） as a soft segment for thermoplastic elastomers.

关键词： Montmorillonite Maghnite ring opening polymerization THF

SYNTHESIS OF POLY(GLUTAMIC ACID-co-ASPARTIC ACID) VIA COMBINATION OF N-CARBOXYANHYDRIDE ring opening polymerization WITH DEBENZYLATION

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Chinese Journal of Polymer Science 2013年第12期31卷 1706-1716页

作者： Wei-xi Yang Ling-ling Wang Han Zhu Ri-wei Xu 吴一弦 State Key Laboratory of Chemical Resource Key Laboratory of Carbon Fiber and Functional Polymers(Ministry of Education)Beijing University of Chemical Technology

The random copolymers of glutamic acid （LG） and aspartic acid （ASP）, poly（LG-co-ASP）, with designed compositions could be successfully synthesized via combination of N-carboxyanhydride ring opening copolymerization with debenzylation. ring opening copolymerizations of y：benzyl-L-glutamate N-carboxyanhydride （BLG-NCA） and β-benzyl-Laspartate N-carboxyanhydride （BLA-NCA） were carried out by using different amines including triethylamine （TEA）, diethylamine, n-hexylamine （NHA）, triphenylamine, diphenylamine or aniline as initiators. All the 6 amines were highly efficient to get well-defined poly（BLG-co-BLA） copolymers with designed compositions although the polymerizations proceeded via different mechanisms （normal amine mechanism or/and activated monomer mechanism）, which are based on chemical structure of amines. The molecular weights of poly（BLG-co-BLA） copolymers could be mediated by both TEA concentration and polymerization time. Then, debenzylation ofpoly（BLG-co-BLA） copolymers was conducted to prepare the corresponding hydrophilic random eopolymers of poly（LG-co-ASP） with a-subunit structure in ASP structural units. The contents of LG structural units in poly（LG-co-ASP） copolymers matched with those of BLG-NCA in NCA-monomer feeds in ring opening copolymerizations initiated by NHA or TEA and were closed to the theoretical line. The diblock copolymer of poly（BLG-b-BLA） could also be synthesized via living NCA ring opening copolymerization by sequential addition of BLG- NCA and BLA-NCA.

关键词： Peptide ring opening polymerization Copolymer Glutamic acid Aspartic acid.

CATIONIC ring-opening polymerization OF TETRAHYDROFURAN WITH KEGGIN-TYPE HETEROPOLYCOMPOUNDS AS SOLID ACID CATALYSTS

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Chinese Journal of Polymer Science 2010年第3期28卷 305-310页

作者： Ahmed Aouissi Salim Salem Al-Deyab Hassan Al-Shehri Chemistry Department College of ScienceKing Saud UniversityRiyadhKSA

Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, （NH4）3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of the counter-cation （H＋, NH4＋） and the peripheral atoms （Mo, W） on the polymerization were investigated. It has been found that when the protons of H3PMo12O40·13H2O were replaced by the ammonium cations the polymerization rate decreased dramatically. Whereas, when the peripheral atoms （Mo） were replaced by their homologous （W）, the polymerization rate increased twofold. As for the viscosity average molecular weight （My） of polymer products, it was found that the high molecular weight （7930） was obtained by using H3PW12O40·13H2O. The molecular weight （My） obtained by H3PMo12O40·13H2O and （NH4）H3PMo12O40·13H2O was 6470 and 6810, respectively.

关键词： Tetrahydrofuran Heteropoly compounds ring opening polymerization Cyclic ether Solid acid

EFFECTS OF MOLECULAR WEIGHT ON THERMAL RESPONSIVE PROPERTY OF PEGYLATED POLY-L-GLUTAMATES

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Chinese Journal of Polymer Science 2013年第2期31卷 201-201,202-210页

作者： Shusheng Zhang Chongyi Chen 李志波 Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences

We investigated the ring opening polymerization （ROP） of di- and tri-ethylene glycol monomethyl ether functionalized L-glutamate N-carboxyanhydrides （NCAs） using hexamethyldisilazane （HMDS） as primary initiator and 1,5,7-triazabicyclo-[4.4.0]dec-5-ene （TBD） as co-initiator. The binary initiator system afforded a living ROP for these pegylated NCAs, and a series of homopolypeptides with controlled molecular weight （MW） and low polydispersity were obtained. We then systematically studied the helical content and clouding point （CP） dependence on polypeptide MW using circular dichroism （CD） spectroscopy and turbidity measurements, respectively. We found that the helical content of both homopolypeptides increased with MW, but the triethylene glycol functionalized poly-L-glutamate （poly-L-EG3Glu） intended to form more stable or-helical structure than diethylene glycol functionalized counterpart （poly-L-EG2Glu） at similar MW. Accordingly, the CP of poly-L-EG2Glu with known end group has strong dependence on its helical content, which is essentially determined by MW. Our results suggested that the thermal responsive properties of these unique pegylated poly- L-glutamates not only rely on their chemical structure but also on their secondary structures, wh^ch is different from conventional thermal responsive polymers.

关键词： N-carboxyanhydride （NCA） ring opening polymerization Polypeptide Helicity Thermal responsive.

Synthesis and Characterization of Nano Ag End Capped L-Cysteine Bridged Diblock Copolymer

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Chinese Journal of Polymer Science 2015年第10期33卷 1404-1420页

作者： M.Jeyapriya B.Meenarathi L.Kannammal S.Palanikumar R.Anbarasan Department of Polymer Technology Kamaraj College of Engineering and Technology

The target of the present investigation is synthesis and characterization of an amphiphilic diblock copolymer with antibacterial property. ring opening polymerization （ROP） of ε-caprolactone （CL） and tetrahydrofuran （THF） was carried out under inert atmosphere by using L-cysteine as a bridging agent in the presence of stannous octoate （SO） as a catalyst. The nano silver end capped diblock copolymer was synthesized by in situ method. Thus obtained nano silver end capped L-cysteine bridged diblock copolymer was characterized by various analytical methods like Fourier transform infrared （FTIR） spectroscopy, nuclear magnetic resonance （NMR） spectroscopy, circular dichroism （CD）, fluorescence spectroscopy, gel permeation chromatography （GPC）, X-ray photoelectron spectroscopy （XPS）, thermogravimetric analysis （TGA）, differential scanning calorimetry （DSC）, field emission scanning electron microscopy （FESEM）, high resolution transmission electron microscopy （HRTEM） and zeta potential. The antimicrobial property of the nano silver end capped diblock copolymer against e-coli was tested.

关键词： ring opening polymerization Amphiphilic diblock copolymer Synthesis XPS HRTEM

SYNTHESIS AND polymerization OF 2-OXO-3-METHYLENE-5, 6-DIPHENYL-1,4-DIOXAN

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Chinese Journal of Polymer Science 1994年第3期12卷 284-289页

作者：冯品珍鲁剑涛 Chemistry Departmemt Graduate School Academia Sinica Beijing 100039

A new cyclic monomer, 2-oxo-3-methylene-5, 6-diphenyl-1, 4-dioxan, was synthesized. Thestructure of the intermediates and the monomer were determined by IR,~1H NMR,^(13)C NMR andelemental analysis. This new monomer is different from other cyclic monomers in this series,it isa solid (mp 108--109℃)and not very reactive, but still can undergo free radical ring-openingpolymerization. The free radical polymerization was carried out at 130℃. The structure of theresulting polymer was discussed and charaterized by IR, ~1H NMR, ^(13)C NMR and elementalanalysis. The molecular weight of the polymer was estimated by viscosity determination.

关键词： Free radical ring opening polymerization Cyclic acrylate 1, 4-Dioxan

SYNTHESIS AND FREE RADICAL polymerization OF 2-OXO-3-METHYLEN E-5-PHENYL-1,4-DIOXAN

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Chinese Journal of Polymer Science 1993年第2期11卷 153-157页

作者：冯品珍 Chemistry Department Graduate School Academia Sinica Beijing 100039

The novel cyclic monomer, 2-oxo-3-methylene-5-phenyl-1,4-dioxan, was synthesized by a set of reactions. Several intermediates were prepared and characterized in order to determine the monomer structure. The presence of chiral centers in the intermediates and resulting monomer makes it complicated to separate , purify and characterize them. It is a very reactive monomer which will polymerize even at room temperature if expose to moisture and air. This monomer can undergo essentially quantitative flee radical ring opening polymerization. The driving force for ring opening is the formation of new carbonyl group and benzylic radical. The monomer and polymer structure were established by IR, ~1H NMR, ^(13)C NMR and elemental analysis or high resolution mass spectrum. The molecular weight of the resulting polymer was estimated by viscosity determination.

关键词： Free radical ring opening polymerization Cyclic acrylate

SYTHESIS AND ANIONIC polymerization OF 2-METHYL-2-METHOXYCARBONYL-5-METHYLENE-1, 3-DIOXOLAN-4-ONE

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Chinese Journal of Polymer Science 1995年第1期13卷 35-40页

作者：冯品珍 Department of Chemistry Graduate School Academia Sinica P. O. Box 3908Beijing 100039

A new cyclic monomer, 2-methyl-2-methoxycarbonyl-5-methylene-1,3-dioxolan-4-one,was synthesized successfully. The monomer and intermediate were characterized by ~1H NMR, ^(13)CNMR, INEPT(Intensive Nuclei Enhanced by Polarization Transfer) technique, IR and elementalanalysis. Anionic polymerization of the monomer was carried out in anhydrous THF at -70℃,and 9-fluorenyllithium was used as initiator. The polymer structure was determined by IR, NMRand elemental analysis. Molecular weight of the polymer was estimated by viscosity measurementin DMSO at 30℃.

关键词： Anionic polymerization ring opening polymerization Cyclic monomer