Composites Research

The Korean Society for Composite Materials (한국복합재료학회)
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Effect of Combined Environmental Factors on Degradation Behavior of Carbon Fiber/Epoxy Composites

복합적인 환경인자의 영향에 따른 탄소섬유/에폭시 복합재의 열화 특성

  • 황영은 (금오공과대학교 기계공학과 대학원) ;
  • 이길형 (금오공과대학교 기계공학과 대학원) ;
  • 윤성호 (금오공과대학교 기계공학부)
  • Published : 2009.10.31
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Abstract

Thermal analysis properties and chemical structure of carbon fiber/epoxy composites under environmental exposure were examined using an accelerated aging tester which can simulate real weather conditions such as temperature, moisture and ultraviolet. The composite specimens were exposed to combined environmental factors up to 3000 hours. Thermal analysis properties and chemical structure of the composites were evaluated with various exposure times through Modulated DSC and FTIR. According to the results of Modulated DSC, the glass transition temperature increased as exposure time increased due to the formation of network structures in the composites. Also endotherm peaks of enthalpy relaxation related to physical aging that can affect the properties of the composites were observed as exposure time increased. From the results of FTIR, it was found that the location of the peaks was little affected by exposure time, but the intensity of the peaks slightly decreased as exposure time increased due to the curing reaction in the epoxy group.

온도, 수분 및 자외선과 같은 자연환경을 모사할 수 있는 가속노화시험장치를 적용하여 복합적인 환경인자에 노출된 탄소섬유/에폭시 복합재의 열분석 특성과 화학구조분석을 수행하였다. 복합적인 환경인자의 최대 노출시간은 3000시간으로 노출시간에 따른 복합재의 열분석 특성과 화학구조는 Modulated DSE와 FTIR을 통해 조사하였다. Modulated DSC 시험을 통한 연우-결과에 따르면 노출시간이 증가할수록 복합재 내에 치밀한 망사 구조가 형성되어 유리전이온도는 증가함을 알 수 있었다. 또한 노출시간이 증가할수록 복합재의 특성에 영향을 미치는 물리시효가 발생하여 엔탈피 완화현상을 나타내는 흡열 피크가 관찰되었다. 아울러 FTIR 시험을 통해 관찰된 피크의 위치는 노출시간에 큰 영향을 받지 않지만 피크의 세기는 노출시간이 증가할수록 에폭시기에 발생되는 경화 반응으로 인해 점차 감소함을 알 수 있었다.

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References

  1. Ellyin, F. and Maser, R., "Environmental Effects on the Mechanical Properties of Glass-fiver Epoxy Composite Tubular Specimens." Composites Science and Technology, Vol. 64, 2004. pp. 1863-1874 https://doi.org/10.1016/j.compscitech.2004.01.017
  2. Lee, S. Y., Park, C. H., Seo, S. H., Kim, Y. U., Kim, Y. H., Park, Y. H., Choi, H. L., and Moon, K. C., "Durability Test of E-Glass FiberNinylester Resin Composites for Specific Environments," Textile Science and Engineering, Vol. 42, No. 6, 2005, pp. 405-411
  3. Kumar, B. G., Singh, R. P., and Nakamura, T., "Degradation of Carbon Fiber-reinforced Epoxy Composites by Ultraviolet Radiation and Condensation," Journal of Composite Materials，Vol. 36, No. 24, 2002, pp. 2713-2733 https://doi.org/10.1177/002199802761675511
  4. Yoon, S. H., "Evaluation of Durability for Glass Fabric/Phenolic Composites under Salt water Environment." Journal of The Korean Society for Composite Materials, Vol. 18, No. 4, 2005, pp. 27-33
  5. Yoon, S. H., Lee, S. J., and Lee, J. K., "Effects of Comvined Environmental Factor on Mechanical and Thermanl Analysis Properties of Graphite/Epoxy Composites," Transactions of The Korean Society of Mechanical Engineers, Vol13, No. 5, 2002, pp. 1416-1425
  6. Thomas, L. C., "Modulated $DSC^\circledR$ Basics; Optimization of MDSC Experimental Conditions," TA Instruments Technical Paper TP 008, 2005
  7. Kim, J. H., Choi, K. Y., Joo, H. J., Jin, F. L., and Park, S. J., "A Study on the Water Resistance and Thermo-mechanical Behaviors of Epoxy Adhesives," Elastomer, Vol. 40, No.3, 2005, pp. 166-173
  8. Fraga, F., Castro-Diaz, C., Rodriguez-Nunez，E., and Martinez-Agoitos, J. M, "Physical Aging for an Epoxy Network Diglycidyl Ether of Bisphenol A/m-xylylenediamine," Polymer, Vol 44, No. 19, 2003, pp. 5779-5784 https://doi.org/10.1016/S0032-3861(03)00624-4
  9. Kong, E. S-W', "Physical Aging in Epoxy Matrices and Composites," Advances in Polymer Science, Vol. 80, 1980, pp. 125-171 https://doi.org/10.1007/3-540-16423-5_14
  10. Nichols, M. E., Wang, S. S., and Geil, P. H., "Creep and Physical Aging in Polyamideimide Carbon Fiber Composite, "Journal of Macromolecular Science, Part B: Physics. Vol. 29, No. 4, 1990, pp. 303-336 https://doi.org/10.1080/00222349008230373
  11. Cook, W. D., Mehrabi, M., and Edward, G. H., "Aging and Yielding in Model Epoxy Thermosets," Polymer, Vol. 40, No. 5, 1999, pp. 1209-1218 https://doi.org/10.1016/S0032-3861(98)00343-7
  12. Frigione, M., Lettieri, M., and Mecchi，A. M., "Environmental Effects on Epoxy Adhesives Employed for Restoration of Historical Buildings," J of Materials in Civil Engineering, Vol. 18, No. 5, 2006, pp. 715-722 https://doi.org/10.1061/(ASCE)0899-1561(2006)18:5(715)
  13. Lee, J. K., Hwang, J. Y., and Gillham, J. K., "Erasure Below Glass-Transition Temperature of Effect of Isothermal Physical Aging in FuIly Cured Epoxy/Amine Thermosetting System," J. Appl. Polym. Sci., Vol. 81, 2001, pp. 396-404 https://doi.org/10.1002/app.1451
  14. Croll, S. G., Shi, X., and Fernando， B. M. D., "The Interplay of Physical Aging and Degradation during Weathering for Two Crosslinked Coatings," Progress in Organic Coatings, Vol. 61, 2008, pp. 136-144 https://doi.org/10.1016/j.porgcoat.2007.09.024
  15. Deo, B., Hodgkin, J., Krstina, J., Mardel, J., and Tian, W., "Accelerated Aging Versus Realistic Aging in Aerospace Composite Materials. I. The Chemistry of Thermal Aging in a Low-Temperaturε-Cure Epoxy Composite," J Appl Polym. Sci., Vol. 102, 2006, pp. 4291-4303 https://doi.org/10.1002/app.24862
  16. Bockenheimer C., Fata, D., and Possart, W., "New Aspects of Aging in Epoxy Networks. I. Thermal Aging," J. Appl Polym. Sci., Vol. 91 , 2004, pp. 361-368 https://doi.org/10.1002/app.13092
  17. Bockenheimer C., Fata, D., and Possart., "New Aspects of Aging in Epoxy Networks. IIrt,ydrothermal Aging," J. Appl. Polym. Sci., Vol. 91 , 2004, pp. 369-377 https://doi.org/10.1002/app.13093