• Title/Summary/Keyword: fluorinated

Search Result 315, Processing Time 0.021 seconds

Gradient Structure and Surface Property of Fluorinated Polyacrylate and Polyurethane Latex Blend Films (불소화 폴리아크릴레이트-폴리우레탄 라텍스 혼성필름의 그레디언트 구조와 표면성질)

  • Zhu, Min;Chen, Kun;Zhang, Yufang;Wang, Xiangrongm;Zhou, Xiangdong
    • Polymer(Korea)
    • /
    • v.38 no.3
    • /
    • pp.265-271
    • /
    • 2014
  • In order to investigate the characteristics of the gradient fluorinated polyacrylate and polyurethane latex blend films, the fluorinated polyacrylate emulsion and the polyurethane emulsion were synthesized, and then the both emulsions were blended at a series of ratios. The effects of content of the fluorinated polyacrylate on the gradient structure and surface property of the blended films were assessed by AFM, XPS, SEM-EDX and surface free energy measurements. It appeared that, while the content of the fluorinated polyacrylate latex was up to 30%, the fluorinated polyacrylate particles were selectively gathered on the film-air (F-A) and film-glass (F-G) interfaces at room temperature. When the content of the fluorinated polyacrylate was under 30%, the gradient structure of fluorinated component was not evident. The further increasing of fluorinated polyacrylate in the mixed system facilitated the formation and enlargement of gradient structure, but the adhesion of film decreased a little.

Synthesis and Lubrication Properties of Semi-Fluorinated Polyol Esters (불소계 폴리올에스테르의 합성과 윤활 특성)

  • 백진욱;정근우;김영운
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
    • /
    • 2001.06a
    • /
    • pp.149-155
    • /
    • 2001
  • New semi-fluorinated polyol esters were synthesized by condensation reaction of polyols (NPG and TMP) and carboxylic acids such as 2-ethylhexanoic acid, stearic acid and perfluorooctanoic acid. The structures of polyol esters were confirmed by FT-IR and H-NMR etc. And, the fluorinated polyol esters were insoluble in several oils, however, the semi-fluorinated polyol esters were soluble in several oils depended on the structure of polyol esters. The physical properties such as 4-ball wear property and extreme-pressure (EP) properties were characterized by measuring wear scar diameter through ASTM D2266 and by determining the load-carrying through ASTM D2783 method, respectively. As the results, wear scar diameters of oils in which the semi-fluorinated polyol esters were added were not changed compared to those of not added oils. While extreme-pressure properties remarkably Increased with fluorine contents of the esters depended on the structure of acid moiety and polyol moiety. Also, the extreme-pressure property of semi-fluorinated NPG polyol ester in gasoline engine oil was better than that of commercial Teflon coating additive.

  • PDF

Fluorinated Esters Derived from Terpenes

  • Joseph D. Park;Robert L. Settine
    • Journal of the Korean Chemical Society
    • /
    • v.8 no.3
    • /
    • pp.128-130
    • /
    • 1964
  • Fluorinated acid chlorides in the C$_3$ to C$_9$ range were reacted with diols prepared from terpene diacids to give good yields of potentially useful esters. These esters were shown to be of greater stability and low temperature properties than those prepared from fluorinated alcohols and corresponding terpene diacids by direct esterification.

  • PDF

Effect of surface treatments on Single-walled Carbon nanotubes(SWNTs) for Hydrogen storage (수소저장용 단일벽 탄소나노튜브의 표면처리 효과)

  • Lee, Young-Seak;Cho, Se-Ho;Park, Il-Nam
    • Journal of Hydrogen and New Energy
    • /
    • v.16 no.4
    • /
    • pp.343-349
    • /
    • 2005
  • In this study, We had surface-treated single-walled carbon nanotubes (SWNTs) for improving hydrogen storage capacity. The SWNTs were treated by heat treatment, acid treatment and fluorinated at various temperatures. The SWNTs were characterized by Raman spectroscopy and TEM and estimated hydrogen storage capacities at 303K. As shown Raman spectra and TEM images, the structure of fluorinated SWNTs were stable at 423K but changed to the MWNTs-like structure or onion structure over 523K. Hydrogen storage capacity of SWNTs fluorinated at 423K was remarkably increased 2.6 times than that of pristine SWNTs. For SWNTs fluorinated at 573K, the amount of hydrogen adsorbed wasn't increased compared with SWNTs fluorinated at 423K. Therefore, high hydrogen storage capacity of SWNTs could be archived by fluorinated condition at 423K, which was not changed SWNT structure.

Synthesis of Fluorinated Polymer Gate Dielectric with Improved Wetting Property and Its Application to Organic Field-Effect Transistors

  • Kim, Jae-Wook;Jung, Hee-Tae;Ha, Sun-Young;Yi, Mi-Hye;Park, Jae-Eun;Kim, Hyo-Joong;Choi, Young-Ill;Pyo, Seung-Moon
    • Macromolecular Research
    • /
    • v.17 no.9
    • /
    • pp.646-650
    • /
    • 2009
  • We report the fabrication of pentacene organic field-effect transistors (OFETs) using a fluorinated styrene-alt-maleic anhydride copolymer gate dielectric, which was prepared from styrene derivatives with a fluorinated side chain [$-CH_2-O-(CH_2)_2-(CF_2)_5CF_3$] and maleic anhydride through a solution polymerization technique. The fluorinated side chain was used to impart hydrophobicity to the surface of the gate dielectric and maleic anhydride was employed to improve its wetting properties. A field-effect mobility of 0.12 cm$^2$/Vs was obtained from the as-prepared top-contact pentacene FETs. Since various functional groups can be introduced into the copolymer due to the nature of maleic anhydride, its physical properties can be manipulated easily. Using this type of copolymer, the performance of organic FETs can be enhanced through optimization of the interfacial properties between the gate dielectric and organic semiconductor.

Textile Surface Modification by Environmentally Friendly Waterborne Fluorinated Acrylate Copolymer (환경친화형 수분산성 불소 아크릴레이트 공중합체에 의한 섬유 표면개질)

  • Yoo Su-Yong;Kim Jung-Du;Moon Myung-Jun;Suh Cha-Su;Ju Chang-Sik;Lee Min-Gyu
    • Journal of Environmental Science International
    • /
    • v.13 no.10
    • /
    • pp.947-953
    • /
    • 2004
  • Waterborne fluorinated acrylate copolymer (WFAC) for surface modification of textile was synthesized from perfluoroalkyl ethyl acrylate, octadecyl acrylate, glycidyl methacrylate, surfactant and 3,3 methyl-methoxy butanol. The structures of the synthesized WFAC were determinated by FT-IR and $^{19}F-NMR$ analysis. The thermal stability investigated with DSC and TGA was decreased with increasing the content of fluorinated acrylate in the copolymer. However, the particle sizes of WFAC were increased with increasing the content of fluorinated acrylate in the copolymer. The surface energies calculated by contact angles of WFAC were in the range of 29.80$\~$13.41 dyne/cm. On the observing SEM of the textile surface treated with WFAC, the textile was swollen and compacted with increasing the concentration of water repellency agent. WFAC synthesized in this study showed a good water repellency.

A Study on the Knoevenagel Reaction of Fluorinated Carbonyl Compounds (含弗素有機 Carbonyl化合物의 Knoevenagel反應에 關한 硏究)

  • You Sun Kim
    • Journal of the Korean Chemical Society
    • /
    • v.7 no.1
    • /
    • pp.85-90
    • /
    • 1963
  • The Knoevenagel reaction of fluorinated carbonyl compounds, 1,1,1-trifluoro-propanone-2-heptafluoro-butyraldehyde, 1,3-dichloro-1,1,3,3-tetrafluoro-acetone, tetradecafluoro-heptanone-4 and 2,2,2-trifluoro-acetophenone yielded fluorinated ${\beta},{\beta}$-dialkyl-${\beta}$-hydroxy acids. Dehydration of the acids do not give the olefinic acid in the case of the perfluorinated system and gave a lactone. From the consideration of electronic and steric effects a mechanismic path of the reaction via a carbanion intermediate was proposed for the reaction. Preparation of related derivatives are also described.

  • PDF

Adjustable Pretilt Angle of Liquid Crystal Alignment Materials

  • Lin, Song-Shiang;Lee, Chein-Dhau;Su, Ya-Ting;Lee, Yu-Der
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08a
    • /
    • pp.80-82
    • /
    • 2007
  • We have developed a series of fluorinated dimethacrylate copolymers. Our work has covered the synthesized derivatives of alignment materials, characterized the pretilt angle and uniformity of liquid crystal alignment layer. The pretilt angle can be tailored by using the fluorinated copolymer. Excellent uniformity was achieved as shown in experimental results.

  • PDF

Anisotropic Superomniphobic Wettability on Hierarchical Structures of Micro Line Array Combined with Fluorinated Wax (C24F50)

  • Jeon, Deok-Jin
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.209.2-209.2
    • /
    • 2014
  • In recent years, researches about hydrophobic and hydrophilic surfaces have been executed however their other effects have not been researched enough. In this paper, the fabrication method of hierarchical structures of micro line array combined with fluorinated wax for anisotropic superomniphobic wettability is presented. We have achieved anisotropic and superomniphobic surface via simple two step methods, which are maskless photolithography and wax deposition. In order to prove how to provide those characteristics, SEM, contact angle measurement tool and X-ray diffraction are used. Fluorinated wax is crystalized self-assembly and it is subordinated on micro line array so that it is able to display anisotropic wettability. Understanding on anisotropic superomniphobic surface and simple fabrication method has been attracted to apply for lots of applications which range from self-cleaning surface, microfluidic chip, to directionally fluid control device, even in oily fluid.

  • PDF