• Title/Summary/Keyword: Polyacrylonitrile fiber

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The Effect of Processing Parameters on the Diameter of Electrospun Polyacrylonitrile(PAN) Nano Fibers (전기방사한 폴리아크릴니트로 나노섬유의 직경에 미치는 공정인자의 영향)

  • 강영식;김학용;류영준;이덕래;박수진
    • Polymer(Korea)
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    • v.26 no.3
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    • pp.360-366
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    • 2002
  • The electrospinning of polyacrylonitrile dissolved in N,N-dimethyl formamide (DMF) successfully produced nano-scale fibers. The processing parameters such as charged voltage, velocity of collected roller, and tip-to-collector distance (TCD) , affected the ultimate fiber size. At TCD of 5 cm, the average tiber diameter increased with increasing charged voltage because of the more aggregation between fibers due to the remaining DMF solvent on the fiber surface. But, at TCD of 9 cm, the average fiber diameter decreased as the charged voltage was increased because of complete evaporation of DMF. Also, the fiber diameter decreased with increasing the velocity of collected roller. Cross direction width (CWD) of nonwoven mat increased with decreasing the charged voltage and with increasing TCD.

An overview of new oxidation methods for polyacrylonitrile-based carbon fibers

  • Shin, Hye Kyoung;Park, Mira;Kim, Hak-Yong;Park, Soo-Jin
    • Carbon letters
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    • v.16 no.1
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    • pp.11-18
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    • 2015
  • The process of oxidizing polyacrylonitrile (PAN)-based carbon fibers converts them into an infusible and non-flammable state prior to carbonization. This represents one of the most important stages in determining the mechanical properties of the final carbon fibers, but the most commonly used methods, such as thermal treatment ($200^{\circ}C$ to $300^{\circ}C$), tend to waste a great deal of process time, money, and energy. There is therefore a need to develop more advanced oxidation methods for PAN precursor fibers. In this review, we assess the viability of electron beam, gamma-ray, ultra-violet, and plasma treatments with a view to advancing these areas of research and their industrial application.

Surface Modification of Polyacrylonitrile by Low-temperature Plasma (저온플라즈마처리에 의한 폴리아크릴로니트릴의 표면개질)

  • Seo, Eun-Deock
    • Textile Coloration and Finishing
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    • v.19 no.1 s.92
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    • pp.45-52
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    • 2007
  • Polyacrylonitrile(PAN) fiber was treated with low-temperature plasmas of argon and oxygen for surface modification, and its surface chemical structure and morphology were examined by a field emission scanning electron microscope(FESEM) and a Fourier-transform infrared microspectroscopy(IMS). The argon-plasma treatment caused the only mechanical effect by sputtering of ion bombardment, whereas the oxygen plasma brought about a chemical effect on the PAN fiber surface. The experimental evidences strongly suggested that cyclization of nitrile group and crosslinking were likely to occur in the oxygen-plasma treatment. On the other hand, with the argon-plasma treatment, numerous my pits resulted in ranging from several tens to hundreds nanometers in radius. The plasma sensitivity of functional groups such as C-H, $C{\equiv}N$, and O-C=O groups in the PAN fiber was dependent on their chemical nature of bonding in the oxygen-plasma, in which the ester group was the most sensitive to the plasma. Vacuum-ultraviolet(VUV) radiation emitted during plasma treatment played no substantial role to alter the surface morphology.