• Title/Summary/Keyword: functional polymers

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New red light-emitting copolymer based on polyfluorene

  • Cho, Nam-Sung;Hwang, Do-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.721-723
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    • 2002
  • We report a new red light emitting fluorene-based copolymer, poly{9,9-bis(2'-ethylhexyl)fluorene-2,7-diyl-co-2, 5-bis(2-thienyl-1-cyanovinyl}-1-(2'-ethylhexyloxy)-4methoxybenzene-5",5'''-diyl} (PFTCVB). The synthesized copolymers showed the absorption maxima at about 380 nm and the absorption between 425 and 600 nm increased as the fraction of the thiophene-containing monomer (BTCVB) increased. In PL, the emission maxima of the copolymers were red-shifted as the fraction of BTCVB increased, despite the similar absorption characteristics were shown in the UV-visible spectra. The copolymer containing 15 mol% of BTCVB showed a maximum PL and EL emission at 620 and 630 nm.

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분자 각인 막의 선택적 분리 (Selective Separations Using Molecularly Imprinted Membranes)

  • 이정우;박중곤
    • KSBB Journal
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    • 제20권3호
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    • pp.133-141
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    • 2005
  • This review presents the preparation, transport mechanism and application of molecularly imprinted membranes (MIM). Molecular imprinting has now been established as a technique which allows the creation of tailor-made binding sites for many classes of compounds. MIM have some advantages; a high capacity due to a large surface area, faster transport of substrate molecules and faster equilibrium of binding cavities compared to molecularly imprinted particles. MIM were prepared by covalent and non-covalent chemical bonding systems, by interactions between functional monomer and template. MIM can be prepared by in-situ polymerization, wet phase inversion, dry phase inversion, and surface imprinting method. MIM can continuously separate mixtures based on facilitated or retarded diffusion of the template. MIM can change their permeability in the presence of templates. MIM have a potential to be used to separate chiral compounds and materials with similar structures. However the application of MIM by the chemical industries is still in its infancy stages.

3D Pattern Construction and Its Application to Tight-fitting Garments for Comfortable Pressure Sensation

  • Jeong Yeon-Hee;Hong Kyung-Hi;Kim See-Jo
    • Fibers and Polymers
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    • 제7권2호
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    • pp.195-202
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    • 2006
  • Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for garment industry, however, fitting problems still exist. The objectives of the paper is to develop a 2D pattern which fits tightly to the 3D human scan data for sports suits that need comfort and function for maximum performance. In this study, the user graphic interface application software for the semi-automatic garment pattern generation has been implemented using the triangle simplification scheme together with 2D projections of free-falling of 3D surface polygons keeping the original 3D surface area preservation. A typical application of the developed pattern to the functional body suits is presented and verification of the proposed method is also provided.

Phase Behavior of Reversibly Associating Star Copolymer-like Polymer Blends

  • June Huh;Kim, Seung-Hyun;Jo, Won-Ho
    • Macromolecular Research
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    • 제10권1호
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    • pp.18-23
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    • 2002
  • We theoretically consider blends of two monodisperse one-end-functionalized homopolymers (denoted by A and B) capable of forming clusters between functional groups (stickers) using weak segregation theory. In this model system resulting molecular architectures via clustering resemble star copolymers having many A- and B-arms. Minimizing the total free energy with respect the cluster distribution, the equilibrium distribution of clusters is obtained and used for RPA (Random Phase Approximation) equations as input. For the case that polymers are functionalized by only one kind of sticker, the phase diagrams show that the associations promote the macrophase separation. When there is strong affinity between stickers belonging to the different polymer species, on the other hand, the phase diagram show a suppression of the macrophase separation at the range of high temperature regime, as well as the phase coexistence between a disordered and a mesoscopic phase at the relatively lower temperatures.

Syntheses and Thermal Properties of 5,10-Disubstituted-2,3,7,8-tetracyano-5,10-dihydrodipyrazino [2,3-b:2′,3′-el pyrazines and Polymeric Porphyrazines Derived from 2,3-Dichloro-5,6-dicyanopyrazine

  • Jaung, Jae-yun;Kim, Sung-Dong
    • Fibers and Polymers
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    • 제1권2호
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    • pp.71-75
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    • 2000
  • Intermolecular cyclization of 2-alkylamino-3-chloro-5,6-dicyanopyrazine 2 in the presence of tributylamine in N,N-dimethylformamide (DMF) gave 5,10-disubstituted-2,3,7,8-tetracyano -5,10-dihydrodipyrazino〔2,3-b:2',3'-e]pyrazines 3, which showed strong mesomorphic property and were anticipated as new chromophoric system for functional dye materials. Absorption spectra, fluorescent properties and other physical properties were correlated with their chemical structures. Vanadyl oligomeric porphyrazine with long alkyl groups synthesized from 3 had satisfactory solubility in tetrahydrofuran (THF), diethyl ether and dimethylsulfoxide (DMSO). The syntheses and characterization of vanadyl polymeric porphyrazines derived from 3 with long alkyl groups are reported.

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Molecularly Imprinted Polymers for Solid-Phase Extraction of Sarcosine as Prostate Cancer Biomarker from Human Urine

  • Hashemi-Moghaddam, Hamid;Rahimian, Majid;Niromand, Bahman
    • Bulletin of the Korean Chemical Society
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    • 제34권8호
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    • pp.2330-2334
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    • 2013
  • A highly selective molecularly imprinted polymer (MIP) for sarcosine, a cancer marker, was prepared and its use as solid-phase extraction (SPE) sorbent material was demonstrated. The MIP was prepared by a very simple procedure using methacrylic acid as functional monomer and a mixture acetonitrile/water (4/1, v/v) as porogen, overcoming in this way the problems usually related to the imprinting of biological polar compounds. The MIP was tested in batch experiments in order to evaluate its binding properties and then used as SPE sorbent for the selective clean-up and pre-concentration of sarcosine. The extraction protocol was successfully applied to the direct extraction of sarcosine from spiked human urine indicating that the MIP allowed sarcosine to be pre-concentrated while simultaneously interfering compounds were removed from the matrix.

Carboxylated Nitrile Elastomer/Filler Nanocomposite: Effect of Silica Nanofiller in Thermal, Dynamic Mechanical Behavior, and Interfacial Adhesion

  • Mahaling R. N.;Jana G. K.;Das C. K.;Jeong, H.;Ha C. S.
    • Macromolecular Research
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    • 제13권4호
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    • pp.306-313
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    • 2005
  • Surface modified nanofillers are often used as curative-cum reinforcing agents for functional polymers. The polymer nanofiller interaction depends on the curative systems used. In the present study the carboxylic group of the carboxylated nitrile elastomer participated in the reaction with Zn-ion coated nanosilica filler producing a type of ionomeric elastomer. The interaction at the molecular level thus produced a high modulus vulcanizate. In this case, the S and MBT system, as curative, had an edge over the MDA and DPG curative system. Interfacial adhesion was enhanced in the presence of Zn-ion-coated nanosilica filler associated with dynamic mechanical behavior. The inferior properties obtained in the case of the MDA and DPG curative system were due to the decreased reactivity of the silica surface, thus reducing interfacial adhesion.

촉매공정에서 양이온 교환 분리막의 응용 (The Application of Perfluorinated Cation-exchange Membrane in the Catalytic Process)

  • 변홍식
    • 멤브레인
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    • 제2권1호
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    • pp.49-58
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    • 1992
  • Functionalized organic polymers have been used as supports for heterogenized homogeneous catalytic process[1]. Sprcific advantages of using these resins as support reagents have been reviewed[2-4]. These include: -ease of by-product separation from the main reaction product usuallyby simple filtration. -prevention of intermolecular reaction of reactive species or functional groups by simulating high dilution conditions[5]. -utility of the "fish-hook" principle in which a minor component in fished out of a large excess substrate by the insoluble polymer[6]. -the possibility of reusing recovered reagents as well as eliminating the use of volatile or noxious substances[7]. Catalysis by ion-exchange membranes is perhaps one of the latest examples of the use of a polymer-supported species. Conceptually, catalysts on membrane supports offer several possible advantages over traditional powder type systems. They are: (1) Membranes immobilize the catalyst, preventing agglomeration. (2) Filtration is unnecessary for the catalyst separation and so complete catalyst recovery is facilitated. (3) Catalytyic and separation processes can be combined, allowing membrane supported catalysts for the continous flow reactors. reactors.

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선택적 분리를 위한 분자 각인 고분자의 설계 및 응용 (Design and Applications of Molecularly Imprinted Polymers for Selective Separations)

  • 정수환;오창엽;서정일;박중곤
    • KSBB Journal
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    • 제16권2호
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    • pp.115-122
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    • 2001
  • Molecular imprinting has now been established as a technique which allows the creation of tailor-made binding sites for many classes of compounds. MIPs were prepared by covalent and non-covalent chemical bonding systems, by interactions between functional monomer and template. The shape of MIP is divided to particle and membrane. MIP membranes can be prepared by surface imprinting, in-situ polymerization, wet phase inversion and the dry phase inversion method. MIPs have been mainly used for analytical separation and biosensor systems to separate and detect chiral compounds and materials with similar structures. However the application of MIP by the chemical industries is still in its infancy stages. This review summarizes the preparative characteristics and applications of MIP with respect to chiral separations and biosensors.

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새로운 광굴절재료의 제작 및 특성 (Synthesis and Properties of the New Photorefractive Material)

  • 민완기;김남오
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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    • pp.120-124
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    • 2002
  • Considerable progress has been made in organic photorefractive materials, since the first observation of photorefractive phenomena from organic materials. Within recent years, a large number of organic photorefractive materials, especially amorphous materials. have been developed based on polymeric composites, fully functional polymers and the multifunctional chromophore approach. Among these organic photorefractive materials, some of them containing carbazole components as a charge transporting function have been demonstrated to exhibit high performance photorefractive effects. The carbazole building blocks with charge transporting functionality or multifunctions play a very important role in photorefraction and have been widely used in the molecular design approach to new organic photo- refractive materials.

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