A study on the Condition of Pyrolysis of Coal Tar Pitch to Form the Mesophase as a Matrix Precursor of Carbon/Carbon Composites

탄소/탄소 복합재 매트릭스 전구체인 이방성 메조페이스 형성을 위한 콜타르 핏치의 열분해 조건 연구

  • 정형진 (명지대학교 무기재료공학과) ;
  • 정윤중 (명지대학교 무기재료공학과) ;
  • 조동환 (금오공과대학교 고분자공학과) ;
  • 임연수 (명지대학교 무기재료공학과) ;
  • 김기원 (명지대학교 무기재료공학과)
  • Published : 1997.09.01

Abstract

Coal tar pitch was used to study the effect of the pyrolysis conditions to produce mesophase pitch used as a matrix precursor for carbon/carbon composites. The pyrolysis conditions were presented in all cases that the total pressure was 1 atm and the first stage temperature was changed from 25$0^{\circ}C$ to 34$0^{\circ}C$ to remove the low molecular weight compounds in the pitch, and then, heated to 40$0^{\circ}C$ to form anisotropic mesophase as the second stage temperature. The first stage temperature was very affected to form resulting anisotropic mesophase pitch. The resulting mesophase pitches show a significantly increased anisotropic contents upto 30$0^{\circ}C$. However, the contents of mesophase were decreased above 30$0^{\circ}C$. It was the reason that the first stage temperature had been control the number of free radicals to react the aromatic compounds in the pitch to form high molecular weight compound. Therefore, the two stage pyrolysis method could be very effectively used to control various contents of anisotropic polyaromatic mesophase compared to continuous to continuous heating method.

Keywords

References

  1. Carbon v.31 no.5 Carbon-Fiber Reinforced Carbon Composites Fabricated with Mesophase Pitch K. Christ;K. J. Huttinger
  2. Chemistry and Physics of Carbon v.4 The Formation of some Graphitizing Carbons J. D. Brooks;G. H. Taylor;P. L. Walker Jr(ed.)
  3. Carbon v.34 no.5 Coal-Tar Pitch as a Matrix Precursor for 2-D C/C Composites P.D.Matzinos;J.W.Patrick;A.Walker
  4. Carbon Fiber Composites Structure of Carbon Fibers D. D. L. Chung
  5. U. S. Patent 19, No.4.208.267 Forming Optically Anisotropic Pitches R. J. Difendof
  6. Carbon-Carbon Composites G. Savage
  7. U.S. Patent 4,005,183 High Strength Carbon Fibers Produced from Mesophase Pitch L. S. Singer;High Modulus
  8. J. Mat. Sci. v.21 Preparation of Anisotropic Mesophase Pitch by Carbonization Under Vacuum Y. D. Park;Y. Korai;I. Mochida
  9. Carbon v.23 no.1 Preparation and Properties of Carbonaceous Mesophase-1, Soluble Mesophase Produced from A240 and Coal Tar Pitch Y. Korai;I. Mochida
  10. Progress in solid state chemistry v.9 The formation of microstructure in graphitizable materials J. L. White;J. O. McCaldin(ed.);G. Somorjar(ed.)
  11. U.S. Patent 4,017,327 Process for Producing Mesophase Pitch I. C. Lewis;E. R. Mchenry;L. S. Singer
  12. Fuel v.70 no.2 Effect of Processing Technology on Mesophase Structure Z. Weishauptova;J. Medek
  13. J. of Materials Science v.25 no.12 Comparative Evaluation of Mcsophase Pitches Derived from Coal Tar and FCC-DO I. Mochida;H. Toshima;Y. Korai;T. Varga
  14. Carbon v.29 no.7 Mechanism of Anisotropy Occurrence in a Pitch Precursor of Carbon Fibers: Part Ⅰ-Pitches A and B K. Lafdi;S. Bonnamy;A. Oberlin