• Morphological Behavior of Oxy-PAN Fiber upon pH Variation
  • Nam JD, Kim JC, Kim HJ, Yoo DG, Jung CJ, Lee YK, Kim KJ
  • Oxy-PAN 섬유의 산도 변화에 대한 형태학적 거동 특성
  • 남재도, 김재철, 김현주, 유동국, 정창조, 이영관, 김광진
Abstract
Oxidized-polyacrylonitrile (oxy-PAN) was prepared by oxidation of PAN fiber at 240 ℃, followed by base catalyzed hydrolysis reaction. The chemical structure of PAN fiber in various pH conditions was characterized by 13C-NMR spectroscopy. The characteristic contraction and expansion behavior of oxy-PAN fiber was observed in acidic and basic medium, respectively. In basic condition, water molecules might be absorbed into the fiber with the movement of charge balancing Na(+) ion, on the other hand, the water molecules seemed to be expelled in acidic condition to result in contraction. It was also observed that the facile chemical modification occurred due to free diffusion of aqueous reagent into the hydrophilic PAN fiber, and the morphology was affected by pH condition.

일반 PAN 섬유를 240 ℃에서 산화시킨 후 1 N NaOH 수용액에서 가수분해시켜 oxidized-PAN 섬유 (oxy-PAN)를 제조하였다. 산과 염기용액에서의 oxy-PAN 섬유의 구조를 13C-NMR 분광분석법을 이용하여 분석하였다. 가수분해에 의하여 -COOH 기를 포함하는 oxy-PAN 섬유는 산과 염기 수용액에서 수축 및 팽창 거동을 하였는데, 염기성 수용액에서는 반대전하로 작용하는 Na(+)이온이 물 분자와 함께 섬유 내부로 침투하면서 팽창하였으며, 산성 수용액에서는 Na(+) 이온이 물 분자와 함께 섬유 외부로 축출되면서 수축하였다. 친수성의 섬유내부로 산/염기 작용기가 자유롭게 침투하여 oxy-PAN 섬유의 화학적인 구조는 쉽게 변화된다는 것을 확인하였으며, 모폴로지도 pH에 의하여 영향을 받는다는 것을 관찰하였다.

Keywords: oxy-PAN; chemical modification; expansion; contraction

References
  • 1. Lee HS, Park JS, Cho SM, Cho SH, J. Korea Fiber Soc., 29(12), 835 (1992)
  •  
  • 2. Henrici-Olive G, Olive S, Adv. Polym. Sci., 32, 123 (1979)
  •  
  • 3. Sawant S, Morawetz H, Macromolecules, 17, 2427 (1984)
  •  
  • 4. Schreyer HB, Gebhart N, Kim KJ, Shahinpoor M, Biomacromolecules, 1, 642 (2000)
  •  
  • 5. Shiga T, Kurauchi T, J. Appl. Polym. Sci., 39, 2305 (1990)
  •  
  • 6. Doi M, Matsumoto M, Hirose Y, Macromolecules, 25, 5504 (1992)
  •  
  • 7. Ossda Y, Okuzaki H, Hori H, Nature, 355, 242 (1992)
  •  
  • 8. Shahinpoor MProceedings of the 1993 SPIE Conference on Smart Structure and Materials, Albuquerque, NM, No. 1916, p. 40-50, SPIE, Bellingham, WA (1993)
  •  
  • 9. Hirai M, Hirai T, Sukumoda A, Nemoto H, Amemiya Y, Kobayasi K, Ueki T, J. Chem. Soc.-Faraday Trans., 91, 473 (1995)
  •  
  • 10. Bohon K, Krause S, J. Polym. Sci. B: Polym. Phys., 36(6), 1091 (1998)
  •  
  • 11. Umemoto S, Okui N, Sakai TPolymer Gels, Eds. by D.DeRossi, et al., p. 257, Plenum Press, New York (1991)
  •  
  • 12. Xue T, McKinney M, Wilkie C, Polym. Degrad. Stabil., 58, 193 (1997)
  •  
  • 13. Surianarayanan M, Vijayaraghavan R, Raghavan KV, J. Polym. Sci. A: Polym. Chem., 36(14), 2503 (1998)
  •  
  • 14. Pouchly J, Biros J, Benes S, Macromol. Chem., 80, 745 (1979)
  •  
  • 15. Hoeve CAJ, Tata AS, J. Phys. Chem., 82, 1660 (1978)
  •  
  • 16. Rodehed C, Randy B, J. Appl. Polym. Sci., 32, 3309 (1986)
  •  
  • 17. Haldankar GS, Spencer HG, J. Appl. Polym. Sci., 37, 3137 (1989)
  •  
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This Article

  • 2002; 26(4): 492-500

    Published online Jul 25, 2002

  • Received on May 2, 2002
  • Accepted on May 31, 2002