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Miktoarms hyperbranched polymer brushes:One-step fast synthesis by parallel click chemistry and hierarchical self-assembly

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Science China Chemistry 2010年第12期53卷 2461-2471页

作者： HAN Yi & GAO Chao MOE key laboratory of macromolecular synthesis and functionalization Department of Polymer Science and Engineering,Zhejiang University,Hangzhou 310027,China 1. MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Spherical molecular brushes with amphiphilic heteroarms were facilely synthesized by grafting the arms of hydrophobic 2-azidoethyle palmitate and hydrophilic monoazide-terminated poly(ethylene glycol) onto the core of alkyne-modified hyperbranched polyglycerol (HPG) with high molecular weight (Mn=122 kDa) via one-pot parallel click *** parallel click grafting strategy was demonstrated to be highly efficient (～100%),very fast (～ 2 h) and well controllable to the amphilicity of molecular *** adjusting the feeding ratio of hydrophobic and hydrophilic arms,a series of brushes with different arm ratios were readily *** resulting miktoarms hyperbranched polymer brushes (HPG-g-C16/PEG350) were characterized by hydrogen-nuclear magnetic resonance (1H NMR),Fourier transform infrared (FT-IR) spectroscopy,gel permeation chromatography (GPC),and differential scanning calorimetry (DSC) *** spherical molecular brushes showed high molecular weights up to 230 kDa,and thus could be visualized by atomic force microscopy (AFM).AFM and dynamic laser light scattering (DLS) were employed to investigate the self-assembly properties of amphiphilic molecular brushes with closed proportion of hydrophobic and hydrophilic *** brushes could self-assemble hierarchically into spherical micelles,and network-like fibre structures,and again spherical micelles by addition of n-hexane into the dichloromethane or chloroform solution of *** addition,this kind of miktoarms polymer brush also showed the ability of dye loading via host-guest encapsulation,which promises the potential application of spherical molecular brushes in supramolecular chemistry.

关键词： miktoarms molecular brushes hyperbranched polyglycerol amphiphilic self-assembly

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Thermo-responsive stick-slip behavior of advancing water contact angle on the surfaces of poly(N-isopropylacrylamide)-grafted polypropylene membranes

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Science China Chemistry 2010年第1期53卷 183-189,289页

作者： WAN LingShu,MENG XiangLin,YANG YunFeng,TIAN Jing & XU ZhiKang key laboratory of macromolecular synthesis and functionalization,Ministry of Education Department of Polymer Science and Engineering,Zhejiang University,Hangzhou 310027,China 1. Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Wettability of a solid surface is highly important to its practical application,especially for the surface that shows thermoresponsive *** this paper,we describe a thermo-responsive stick-slip behavior of water droplets on the surfaces of poly(N-isopropylacrylamide)(PNIPAM)-grafted polypropylene *** emission scanning electron microscope(FESEM) images elucidate that the morphology of PNIPAM-grafted membrane surface is thermo-responsive,i.e.,the surface becomes rougher above the lower critical solution temperature(LCST) of *** the surface of nascent polypropylene membranes,the water droplet shows a smooth motion resulting in advancing and receding water contact angles of 111° and ～65°,*** the PNIPAM-grafted membrane surfaces,the water droplet shows a stick-slip pattern above the LCST,whereas it advances smoothly below the *** phenomenon is reproducible and can be ascribed to the energy barriers enhanced by the shrink of PNIPAM chains above the *** also find that the slip contact angle decreases from 102° to 92° after several stick-slip *** decrease is attributed to the water adsorption on the grafted PNIPAM layer,which is confirmed by the continuous decrease of the receding water contact angle.

关键词： stick-slip behavior water contact angle thermo-responsive surface poly(N-isopropylacrylamide) polypropylene membrane

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BIODEGRADABLE ALIPHATIC/AROMATIC COPOLYESTERS BASED ON TEREPHTHALIC ACID AND POLY(L-LACTIC ACID):synthesis,CHARACTERIZATION AND HYDROLYTIC DEGRADATION

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Chinese Journal of Polymer Science 2010年第3期28卷 405-415页

作者：方征平 Institute of Polymer Composites Zhejiang UniversityKey Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Lab of Polymer Materials and Engineering Ningbo Institute of TechnologyZhejiang University

Biodegradable aliphatic/aromatic copolyesters, poly（butylene terephthalate-co-lactate）（PBTL） were prepared via direct melt polycondensation of terephthalic acid （TPA）, 1,4-butanediol （BDO） and poly（L-lactic acid） oligomer （OLLA）. The effects of polymerization time and temperature, as well as aliphatic/aromatic moiety ratio on the physical and thermal properties were investigated. The largest molecular weight of the copolyesters was up to 64100 with molecular weight distribution index of 2.09 when the polycondensation was carried out at 230℃ for 6 h. DSC, XRD, DMA and TGA analysis clearly indicated that the degree of crystallinity, glass-transition temperature, melting point, decomposition temperature, tensile strength, elongation and Young＇s modulus were influenced by the ratio between TPA and OLLA in the final copolyesters. Hydrolytic degradation results demonstrated that the incorporation of biodegradable lactate moieties into the aromatic polyester could efficiently improve hydrolytic degradability of the copolymer even though it still had many aromatic units in the main chains.

关键词： Aliphatic/aromatic copolyesters Direct melt polycondensation Biodegradable

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Macromol. Chem. Phys. 3/2011

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macromolecular Chemistry and Physics 2011年第3期212卷

作者： Xu Huang Xiao‐Jun Huang An‐Guo Yu Cang Wang Zheng‐Wei Dai Zhi‐Kang Xu MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Department of Chemistry Zhejiang University Hangzhou 310027 China

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Stimulus responsive fluorescent hyperbranched polymers and their applications

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Science China Chemistry 2010年第12期53卷 2409-2428页

作者： WANG Jian 1,MEI Ju 1,QIN AnJun 1,SUN JingZhi 1 & TANG Ben Zhong 1,2 1 MOE key laboratory of macromolecular synthesis and functionalization Department of Polymer Science and Engineering,Institute of Biomedical Macromolecules,Zhejiang University,Hangzhou 310027,China 2 Department of Chemistry,The Hong Kong University of Science & Technology,Hong Kong,China 1. MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Institute of Biomedical Macromolecules Zhejiang University Hangzhou 310027 China2. Department of Chemistry The Hong Kong University of Science & Technology Hong Kong China

Fluorescent hyperbranched polymers (FHBPs),which combine the versatile fluorescent property with unique characteristics of hyperbranched architecture,are desirable candidates for stimulus responsive *** review demonstrates the structure and environment-dependent emission behaviors of a series of *** active FHBPs showing opposite performance to ACQ effect are used to sensitively detect explosives and a superamplification effect is *** designed FHBPs can complex with metal ions,leading to fluorescence turn-off due to complex quenching *** protonation of amino-containing FHBPs exhibits pH-dependent fluorescence responses to solution *** FHBPs containing responsive moieties are photo-and thermo-sensitive,and show potential applications as smart materials.

关键词： fluorescent hyperbranched polymer explosives and metal ions detection pH responsive optical and thermal sensitive

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Linear Dynamic Viscoelastic Response of Melts for Crosslinkable Polyethylene Insulation Cable Granules During Cross-linking

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Chemical Research in Chinese Universities 2010年第1期26卷 142-147页

作者： YANG Hong-mei YANG Yong-zhu HE Xiao ZHENG Qiang ZHOU Hou-qiang Department of Polymer Science and Engineering Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Zhejiang University Hangzhou 310027 P. R. China Ningbo Dongfang Cable Ltd. Ningbo 315040 R R. China

Two commercial crosslinkable polyethylene insulation cable granules, designed for 110 and 35 kV voltage insulation, with similar crosslinking temperature but different melting temperature, were chosen as experimental samples for examining their linear dynamic responses during cross-linking. It has been found that the gel contents of cable compounds for 110 and 35 kV insulation are almost the same after they have been cross-linked at the same temperature, pressure and time. And the sample melts show the similar dependence of the dynamic storage modulus, G; on strain. On the other hand, the dynamic temperature ramp test and the dynamic time sweep test indicate that the samples exhibit different dynamic viscoelastic responses during their crosslinking. An expression for describing their erosslinking process was proposed via probing rheokinetics of crosslinking for the two samples.

关键词： XLPE Insulation cable Crosslinking Rheological behavior

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Study on the Stability of Ion-exchange Resin Catalysts:Ⅰ. TGA as a Rapid Evaluating Method

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China Petroleum Processing & Petrochemical Technology 2010年第2期12卷 68-74页

作者： Tan Songwei Wang Hongjun Jiang Hongliang Wang Liqun Wilbert Tsao Lin Xiangzhou MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China The Purolite Company 150 Monument Road Bala Cynwyd PA 19004 USA

The thermal stability of five commercial ion-exchange resin catalysts was studied by means of thermal gravimetric analysis （TGA） at elevated temperatures of up to 600℃ and isothermal temperatures in the range of 150℃ and 200 ℃. Resin samples with different initial water contents were also investigated. The study indicated that TGA, as a complementary evaluating method for the plug flow reactor system approach, could be used as a fast analyzing means for study on the thermal stability of ion-exchange resin catalysts. The stoichiometric calculation of the isothermally treated resin catalysts based on the FTIR analysis and acid capacity confirmed that the weight loss of the resins at 150℃ and 200℃ was caused by the desulfonation process and that desulfonation occurred mainly at the para-position of the benzene ring in the resins. H＋ ions and moisture played an important role in the desulfonation process.

关键词： thermal stability ion-exchange resin catalysts TGA desulfonation

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Sterol-containing tetraphenylethenes: synthesis,aggregation-induced emission,and organogel formation

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中国高等学校学术文摘·化学 2010年第3期5卷 325-330页

作者： Yang LIU Jacky W.Y.LAM Faisal MAHTAB Ryan T.K.KWOK Ben Zhong TANG Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina and Department of Polymer Science & EngineeringKey Laboratory of Macromolecular Synthesis and Functionalization of the Ministry of Education

Cholesterol- and stigmasterol-containing tetraphenylethenes (TPEs) (TPE-Chol and TPE-Stig) are facilely synthesized in satisfactory yields by Cu (I)-catalyzed click reaction of 1,2-bis(4-azidomethylphenyl)-1,2-diphenylethene and cholesteryl-4-ethylbenoate and sigmasteryl 11-(4-ethynylphenoxy)undecanoate, respectively. Whereas they are nonluminescent in solution, they become highly emissive when aggregated in the condensed phase. The molecules of TPE-Stig can self-assemble in methanol solution, generating organogels with gelation-induced emission characteristics.

关键词： sterols tetraphenylethenes aggregation-induced emission gel

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Calcium chloride doped zinc-cobalt metal-cyanide complex:Unexpected highly activity towards ring-opening polymerization of propylene oxide

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Chinese Chemical Letters 2010年第8期21卷 897-901页

作者： Yi Jun Huang Xing Hong Zhang Zheng Jiang Hua Guo Rong Qi Qian Jiang College Hangzhou Normal UniversityHangzhou 310012China Key Laboratory of Macromolecular Synthesis and Functionalization of the Ministry of Education Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Inspection & Quarantine Technology Center Ningbo Entry-exit Inspection & Quarantine BureauNingbo 315012China

Highly active calcium chloride（CaCl2） doped Zn-Co^Ⅲdouble metal-cyanide（Ca-DMC） catalysts were firstly ***-DMCs presented a very higher polymer yield（54 kg polymer/g catalyst） at relative low temperature（80-115℃） toward ringopening polymerization（ROP） of propylene oxide（PO） than did DMC catalysts without modification.

关键词： Catalysts Polyethers Ring-opening polymerization Metal-cyanide complex

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synthesis AND CHARACTERIZATION OF COUMARIN MODIFIED REVERSIBLE PHOTO-CROSSLINKABLE HYALURONIC ACID

SYNTHESIS AND CHARACTERIZATION OF COUMARIN MODIFIED REVERSIB...

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第四届国际高分子化学学术讨论会

作者： Liyan Shen Ke Fu Gongyan Liu Qiao Jin Jian Ji MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

Hyaluronic acid(HA)is an acidic polysaccharide with extremely high molecular *** polysaccharide is an important component of extracellular matrix and connective tissues.[1]HA has beenused for medical purposes is aiming at been used as biomaterials,for instances,as drug delivery systems,[2]anti-postoprative adhesion[3]or tisssue engineering scaffold.[4]However,the difficulty in

关键词： synthesis AND CHARACTERIZATION OF COUMARIN MODIFIED REVERSIBLE PHOTO-CROSSLINKABLE HYALURONIC ACID

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