Abstract：In the temperature range of 300-800℃, 40%-50% of the mass lost during the processing of polyacrylonitrile based carbon fiber (PANCF). Understanding the degradation behavior will be valuable in understanding the formation mechanism of pseudo-graphite structure, and providing theoretic basis for producing high performance carbon fiber and increasing the carbonization yield. The simulation of the degradation progress was carried out on the thermogravimetric analyzer (TGA), the results show that there are two degradation steps for PAN fiber stabilized in air, and controlled by cyclization coefficient and oxygen content. The cyclization coefficient and oxygen content are effective to the density of carbon fiber by influencing the degradation behavior, which cause defects in the fiber. The higher cyclization coefficient leads to form less structural defects and higher density of the fiber; on the contrary, the higher oxygen content leads to form more structural defects and lower density of the fiber.
[1] YUSOF N, ISMAIL A F. Post spinning and pyrolysis processes of polyacrylonitrile (PAN)-based carbon fiber and activated carbon fiber: a review [J]. Journal of Analytical and Applied Pyrolysis, 2012, 93:1-13.
[2] USAMI T, ITOH T, OHTANI H, et al. Structural study of polyacrylonitrile fibers during oxidative thermal degradation by pyrolysis-gas chromatography, solid-state 13C nuclear magnetic resonance, and fourier transform infrared spectroscopy [J]. Macromolecules, 1990, 23(9):2460-2465.
[3] JING M, WANG C G, WANG Q, et al. Chemical structure evolution and mechanism during pre-carbonization of PAN-based stabilized fiber in the temperature range of 350-600℃ [J]. Polymer Degradation and Stability, 2007, 92(9):1737-1742.
[4] 张晓崴,覃福作,童元建,等.TGA-FTIR联用技术研究PAN预氧化纤维的热解[J].合成纤维工业,2007,30(4):64-65. ZHANG X W, QIN F Z, TONG Y J, et al. Study on the degradation of pre-oxidized PAN fiber by using TGA-FTIR coupling technique [J]. Synthetic Fiber Industry, 2007, 30(4): 64-65.
[5] RAHAMAN M S A, ISMAIL A F, MUSTAFA A. A review of heat treatment on polyacrylonitrile fiber [J]. Polymer Degradation and Stability, 2007, 92(8):1421-1432.
[6] QIN X Y, LU Y G, XIAO H, et al. A comparison of the effect of graphitization on microstructures and properties of polyacrylonitrile and mesophase pitch-based carbon fibers [J]. Carbon, 2012, 50(12):4459-4469.
[7] XIAO H, LU Y G, ZHAO W Z, et al. The effect of heat treatment temperature and time on the microstructure and mechanical properties of PAN-based carbon fibers [J]. Journal of Materials Science, 2014, 49(2):794-804.
[8] 肖春,侯卫权,邹武,等.热处理温度对炭纤维结构和性能的影响[J].炭素技术,2006,25(6):15-18. XIAO C, HOU W Q, ZOU W, et al. The effect of thermal treatment temperature on the structure and property of carbon fibers [J]. Carbon Technology, 2006, 25(6): 15-18.
[9] PAIVA M C, KOTASTHANE P, EDIE D D, et al. UV stabilization route for melt-processible PAN-based carbon fibers [J]. Carbon, 2003, 41(7):1399-1409.
[10] 宋云鹏,吕永根,秦显营,等.氮气中环化热处理对聚丙烯腈纤维不熔化的影响 [J].材料导报,2009,23(9):54-56. SONG Y P, LV Y G, QIN X Y, et al. The influence of cyclization thermal-treatment under nitrogen to the infusibility of polyacrylonitrile fiber [J]. Materials Review, 2009, 23(9): 54-56.
[11] 张丽珍,吕春祥,吕永根,等.聚丙烯腈纤维在预氧化过程中的结构和热性能转变[J].新型炭材料,2005,20(2):144-150. ZHANG L Z, LV C X, LV Y G, et al. Transformation of structure and thermal performance of polyacrylonitrile fiber during pre-oxidative process [J]. New Carbon Materials, 2005, 20(2): 144-150.
[12] 温月芳,李辉,曹霞,等.聚丙烯腈纤维预氧化程度的表征[J].纺织学报,2008, 29(12):1-5. WEN Y F, LI H, CAO X, et al. Characterization of the pre-oxidative extent of polyacrylonitrile fiber [J]. Journal of Textile Research, 2008, 29(12): 1-5.
[13] 王成国,井敏,王延相,等.碳纤维用聚丙烯腈基预氧丝碳化裂解过程研究进展[J].现代化工,2008,28(7):22-26. WANG C G, JIN M, WANG Y X, et al. Research progress of the carbonizing degradation process of PAN pre-oxidized fiber using for carbon fiber [J]. Modern Chemistry,2008,28(7):22-26.
[14] WATT W. Pyrolysis of polyacrylonitrile [J]. Nature, 1969, 222: 265-266.
[15] WATT W. Nitrogen evolution during the pyrolysis of polyacrylonitrile [J]. Nature Physical Science, 1972, 235: 10-11.
[16] 孙瑾,潘鼎,江绍群,等.用DSC法研究聚丙烯腈纤维的热性能及其预氧化过程[J].中国纺织大学学报,1990,16(1):51-56. SUN J, PAN D, JIANG S Q, et al. Study on the thermal property and the pre-oxidation process of polyacrylonitrile fiber using DSC [J]. Journal of China Textile University, 1990, 16(1): 51-56.
[17] JAWHARI T, ROID A, CASADO J. Raman spectroscopic characterization of some commercially available carbon black materials [J]. Carbon, 1995, 33(11): 1561-1565.
2017, Vol. 45 
