• Title/Summary/Keyword: polymer structure

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Construction of a 2D Co(II) Coordination Polymer with (4,4)-Connected Topology: Synthesis, Crystal Structure, and Surface Photo-electric Property

  • Li, Jia-Ming
    • Bulletin of the Korean Chemical Society
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    • v.35 no.4
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    • pp.1177-1181
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    • 2014
  • A 2D grid-like (4, 4)-connected topology coordination polymer, $[Co(BTA)_2(H_2O)_2]_n$ (1), where HBTA = 2-(1H-benzotriazol-1-yl)acetic acid, has been synthesized by hydrothermal method and characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis and surface photovoltage spectroscopy (SPS). X-ray diffraction analyses indicated that 1 displays octahedral metal centers with secondary building units (SBUs) [$Co(BTA)_2(H_2O)_2$] bridged by the $BTA^-$ ligands. In the crystal, the 2D supramolecular architecture is further supported by $O-H{\cdots}O$, $O-H{\cdots}N$, $C-H{\cdots}O$ hydrogen bonds and ${\pi}{\cdots}{\pi}$ stacking interactions. The SPS of polymer 1 indicates that there are positive response bands in the range of 300-600 nm showing photo-electric conversion properties. There are good relationships between SPS and UV-Vis spectra.

Characteristics of Sulfuric acid corrosion of Recycled PET Polymer Concrete with Different Filler (충전재 변화에 따른 PET 재활용 폴리머 콘크리트의 황산 부식에 관한 특성)

  • Jo Byung Wan;Gu Ja Kap;Park Jong Hwa;Park Seung Kook
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.719-722
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    • 2004
  • Resins using recycled PET offer the possibility of a lower source cost of materials for making useful polymer concrete products. The purposed of this paper is to form a part of reducing the damage of sulfuric acid, through investigating recycled PET polymer concrete, . immersed at sulfuric acid solution for 84 days. Recycled PET PC is excellent chemical resistance, resulting in the role of unsaturated polyester resin which consists of polymer chain structure accomplishes bond of aggregates and filler strongly. Also, Recycled PET PC, used fly-ash as filler, is stronger resistance of sulfuric acid corrosion than $CaCO_3$, because it is composed of $SiO_2$ and very strong glassy crystal structure. Therefore, Recycled PET PC, used fly-ash as filler, is available under corrosion circumstances like sewer pipe or waste disposal plant.

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Synthesis and Properties of Poly(2-ethynyl-N-propargylpyridinium bromide)

  • Gal, Yong Sun;Lee, Won Cheol;Gwi, Tae Rong;Lee, Sang Seop;Bae, Jang Sun;Kim, Bong Sik;Jang, Sang Hui;Jin, Seong Ho
    • Bulletin of the Korean Chemical Society
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    • v.22 no.2
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    • pp.183-188
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    • 2001
  • Ionic conjugated polymer, poly(2-ethynyl-N-propargylpyridinium bromide), was prepared by the cyclopolymerization of 2-ethynyl-N-propargylpyridinium bromide on using various transition metal catalysts, or by thermal methods without adding catalyst. The polymerization of 2-ethynyl-N-propargylpyridinium bromide catalyzed by PdCl2 gave the resulting polymers in relatively high yields. The polymer structure was characterized by various instrumental methods to confirm the conjugated polymer backbone structure carrying cumulated pyridine moiety. The polymers prepared by PdCl2 in DMSO or m-cresol were completely soluble in DMF, DMSO, and formic acid. The inherent viscosities of the resulting polymers were in the range of 0.07-0.19 dL/g. Thermal properties of the polymers were also discussed.

An Experimental Study on Spalling Reduction Methode of Polymer Modified Cement Mortar Using Fiber Cocktail (섬유혼입 공법을 이용한 폴리머 시멘트 모르타르의 폭렬저감방안에 관한 실험적 연구)

  • Kim, Ji-Hoon;Ryu, Dong-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.96-97
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    • 2020
  • Polymer modified cement mortar (PCM) is commonly used as a repair material. However, in high-temperature environments such as fire, it is more likely to explode than cement mortar. The polymer is thermally decomposed at a high temperature to form a gas, and the gas remaining inside the structure increases the internal pressure to generate a burst. When an spalling occurs, the coating is peeled off and dropped, and high temperature is transmitted to the inside of the structure. In severe cases, even the reinforcing bar is exposed, which can lead to the collapse of the structural member due to severe loss of strength. In this study, in order to reduce spalling of PCM, a fiber mixing method was selected from the refractory method to find an appropriate blending ratio of fibers and polymers.

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Synthesis and Characterization of a Tetrathiafulvalene-Based Polymer

  • Lee, Se-Hyun;Wang, Lei;Hwang, Seok-Ho;Lee, Myong-Hoon;Jeong, Kwang-Un
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1451-1456
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    • 2012
  • A novel tetrathiafulvalene (TTF)-based main-chain polymer (6TTF-polymer) was successfully synthesized via a condensation polymerization between a newly synthesized dihydroxy TTF derivative and a malonyl chloride, and its chemical structure was characterized by spectroscopic techniques. Molecular weight of the 6TTF-polymer (9,030 g/mol by gel permeation chromatography) was large enough to form the ductile film. The electrochemical and optical properties of the 6TTF-polymer were further estimated by cyclic voltammetry, ultraviolet and photoluminescence spectroscopes. The highest occupied molecular orbital level ($E_{HOMO}$=-4.79 eV) and band-gap energy ($E_g$=1.91 eV) of the 6TTF-polymer suggested that TTF-based polymer could act as a good electron donating material for the optoelectronic applications.

Characteristics and Ring-Opening Isomerization Polymerization of 2-(1,3,3-Trimethyl-6-azabicyclo[3,2,1]-oct-6-yl)-4,5-dihydro-1,3-oxazoline (TAO) (2-(1,3,3-Trimethyl-6-azabicyclo[3,2,1]-oct-6-yl)-4,5-dihydro-1,3-oxazoline(TAO)의 개환이성화중합과 특성평가)

  • Lee, Chan-Woo;Chung, Jin-Do
    • Polymer(Korea)
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    • v.36 no.3
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    • pp.262-267
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    • 2012
  • 2-(1,3,3-Trimethyl-6-azabicyclo [3,2,1]-oct-6-yl)-4,5-dihydro-1,3-oxazoline (TAO) was polymerized at several conditions to clarify the influence of initiators, alkyl halide ($PhCH_2Br$, $PhCH_2Cl$, MeI) and sulfonate (MeOTf). The reactions were conducted at $100^{\circ}C$ for 24 h. The resultant polymer forms several kinds of structures with different combination of initiators. The sole MeOTf initiator caused chain transfer reaction to form the one-order structure for which the resultant polymer exclusively formed pendant structure, while alkyl halide and MeOTf formed two kinds of structures, pendant and main chain, which is caused by partly-proceeded double isomerization polymerization by highly reactive nucleophilic counter anion of halogen. Merrifield polymer was also utilized as an intiator and copolymerized with TAO, which produced a graft structure.