EXPERIMENTAL
Materials and Characterizations
The monomers, acrylonitrile (AN), methyl acrylate (MA), itaconic acid (IA), initiator AIBN (2,2’-azo-bis-isobutyronitrile) were obtained from Aldrich Co. The dimetylsulfoxide (DMSO) purchased from Yakuri Pure Chemical was used as solvent in this reaction. AN and MA were washed with aqueous NaCl (to remove inhibitor), washed twice with distilled water, and distilled at reduced pressure before use. Samples for differential scanning calorimeter (DSC) experiments were heated to 500 ℃ under nitrogen atmosphere at a heating rate of 10 oC/min. Thermogravimetric analysis (TGA) was performed using a Shimadzu TGA 50 (Shimadzu, Inc.). The samples were heated to 800 ℃ in nitrogen in an electric furnace at a rate of 10 ℃/min. Viscosity measurements were performed at 25 ℃ using a BROOKFIELD viscometer (LVDVII+). Surface layer morphologies were analyzed using a scanning electron microscope (SEM) with Energy-dispersive X-ray (EDX) spectroscopy model Hitachi, S-4700. As-spun and stabilized fibers were sputter-coated with a platinum layer before being subjected to a SEM analysis. The surface functionalities of the copolymer were examined by Fourier transforms infrared spectroscopy (FT-IR, Nicolet 200 instrument). All the samples were analyzed using the KBr pellet technique and scanned in the range from 4000 to 400 cm−1. The yield of the copolymer was determined by the weight % of copolymer on the basis of the total amount of monomer used. Microwave irradiation of the samples was studied by microwave oven (KR-A202B).
Synthesis of PAN Copolymer
Monomer AN, MA, IA put together in a given weight fraction in DMSO solvent in cover tight Teflon bottle, and then the sample was polymerized under microwave irradiation of 100Watt (KR-A202B, Dae Woo, Korea) for various times. After cooling down to room temperature, the polymers washed with methanol until no remaining of solvent and unreacted monomers and finally dried it under vacuum at 70 ℃ for 24h. The copolymer produced from the monomer composition of 90/10(AN/MA) in the presence of 0.1 wt% initiator (AIBN) in DMSO solvent (ratio of total monomer and solvent is 1:2) was identified as AN90MA10(0.1)200%.
Carbon Fiber Preparation
The PAN copolymer was spun into fiber through the using a melt spinning apparatus at melting temperature (DAQSTATION DX1000, YOKOGAWA, Tokyo, Japan). PAN copolymer were heated up to 190 ℃ (5 ℃/min) in nitrogen atmosphere and hold for 30 min. Fibers were initially spun through a round single-hole spinneret having 0.5 mm diameter, and then collected on a aluminum drum located down 52 cm from the spinneret at with average speed at 50 mmin-1. In addition, the melt spun PAN copolymer fibers were dipped in 3 wt% KMnO4 aqueous solution for 4 hours, which is followed by washing with distilled water and dried at room temperature. It was additionally heated up to 280 ℃ in a tubular furnace under nitrogen atmosphere and carbonized at 800 ℃ in nitrogen atmosphere. The overall process of carbon fibers from PAN copolymer is presented in Fig. 9.
Fig. 9.Schematic of preparation process of carbon fiber
참고문헌
- Donnet, J. B.; Bansal, R. C. Carbon Fibers; Marcel Dekker: 1984.
- Fitzer, E. Carbon Fibers and Their Composites; Springer-Verlag: 1985.
- Cato, A. D.; Edie, D. D. Carbon 2003, 41, 1411. https://doi.org/10.1016/S0008-6223(03)00050-2
- Bahl, O. P.; Manocha, L. M. Carbon 1974, 12, 417. https://doi.org/10.1016/0008-6223(74)90007-4
- Johnson, D. J.; Tyson, C. N. J. Phys. D: Appl. Phys. 1969, 2, 787. https://doi.org/10.1088/0022-3727/2/6/303
- Donnet, J. B.; Bansal, R. C. Carbon Fibers, 2nd ed.; Marcel Dekker: 1990.
- Jones, R. M. Mechanics of Composite Materials; McGraw-Hill: 1975.
- Baker, F. S.; Gallego, N. C.; Naskar, A. K.; Baker, D. A. Low-Cost Carbon Fibers; Oak Ridge National Laboratory: 2007.
- Daumit, G. P.; Ko, Y. S.; Slater, C. R.; Venner, J. G.; Young, C. C. U.S. Patent 4935180, 1990.
- Furuta, S.; Katsuki, H.; Komarneni, S. J. Porous Materials 2001, 8, 43. https://doi.org/10.1023/A:1026522401784
- Uguina, M. A.; Serrano, D. P.; Sanz, R.; Castillo, E. Proc. 12th Intern.: Zeolite Conference 1998.
- Perreux, L.; Loupy, A. Tetrahedron 2001, 57, 9199. https://doi.org/10.1016/S0040-4020(01)00905-X
- Lidstrom, P.; Tirney, J.; Wathey, B.; Westman, J. Tetrahedron 2001, 57, 9225. https://doi.org/10.1016/S0040-4020(01)00906-1
- Park, J. H.; Park, S. H.; Jhung, S. H. J. Korean Chem. Soc. 2009, 53, 553. https://doi.org/10.5012/jkcs.2009.53.5.553
- Choi, K. Y.; Conner, W. C. J. Korean Ind.: Eng. Chem. 2007, 18, 344.
- Kim, J. H.; Heo, J.; Kang, B. M.; Son, D. H.; Lee, G. D.; Hong, S. S.; Park, S. S. J. Korean Ind.: Eng. Chem. 2009, 20, 154.
- Barbier-Baudry, D.; Brachais, L.; Cretu, A.; Gattin, R.; Loupy, A.; Stuerga, D. Environ. Chem. Lett. 2003, 1, 19. https://doi.org/10.1007/s10311-002-0005-4
- Kyotani, T.; Nakazaki, S.; Xu, W. H.; Tomita, A. Carbon 2001, 39, 782. https://doi.org/10.1016/S0008-6223(01)00013-6
- Mawhinney, D. B.; Naumenko, V.; Kuznetsova, A. Chem. Phys. Lett. 2000, 324, 213. https://doi.org/10.1016/S0009-2614(00)00526-1
- Mawhinney, D. B.; Naumenko, V.; Kuznetsova, A.; Yates, Jr.; John, T.; Liu, J.; Smalley, R. E. J. Am. Chem. Soc. 2000, 122, 2383. https://doi.org/10.1021/ja994094s
- Hernadi, K.; Siska, A.; Thien-Nga, L.; Forro, L.; Kiricsi, I. Solid State Ionics 2001, 141-142, 203. https://doi.org/10.1016/S0167-2738(01)00789-5
- Hwang, K. C.; J. Chem. Soc.: Chem. Comm. 1995, 2, 173.
- Gupta, A.; Harrison, I. R. Carbon 1996, 34, 1427. https://doi.org/10.1016/S0008-6223(96)00094-2
- Esrafilzadeh, D.; Morshed, M.; Tavanai, H. Synth. Met. 2009, 159, 267. https://doi.org/10.1016/j.synthmet.2008.09.014
- Maradura, S. P.; Kim, C. H.; Kim, S. Y.; Kim, B. H.; Kim, W. C.; Yang, K. S. Synth. Met. 2012, 162, 453. https://doi.org/10.1016/j.synthmet.2012.01.017
- Fitzer, E.; Muller, D. J. Carbon 1975, 13, 63. https://doi.org/10.1016/0008-6223(75)90259-6
- Bhat, G. S.; Abhiraman, A. S.; Cook, F. L.; Peebles Jr., L. H. J. Appl. Polym. Sci. 1993, 49, 2207. https://doi.org/10.1002/app.1993.070491217
- Shimoda, K.; Park, J.-S.; Hinoki, T.; Kohyama, A. Appl. Surf. Sci. 2007, 253, 9450. https://doi.org/10.1016/j.apsusc.2007.06.023
- Mathur, R. B.; Mittal, J.; Bahl, O. P. J. Appl. Polym. Sci. 1993, 49, 469. https://doi.org/10.1002/app.1993.070490311
- Wangxi, Z.; Jie, L. Journal of Wuhan University of Technology - Mater. Sci. Ed. 2006, 21, 44.
- Kubo, S.; Uraki, Y.; Sano, Y. Carbon 1998, 36, 1119. https://doi.org/10.1016/S0008-6223(98)00086-4