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Korean Carbon Society (한국탄소학회)
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High Char-Yield in AN-AM Copolymer by Acidic Hydrolysis of Homopolyacrylonitrile

  • Cheng, Run (State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology) ;
  • Zhou, You (Department of Chemistry and Chemical Engineering, Anyang Normal University) ;
  • Wang, Jing (Department of Chemistry and Chemical Engineering, Anyang Normal University) ;
  • Cheng, Yumin (Department of Chemistry and Chemical Engineering, Anyang Normal University) ;
  • Ryu, Seungkon (Department of Chemical Engineering, Chungnam National University) ;
  • Jin, Riguang (State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology)
  • Received : 2012.08.31
  • Accepted : 2012.12.17
  • Published : 2013.01.31
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Abstract

Acrylonitrile (AN)-acrylamide (AM) copolymers were prepared by nitric acidic hydrolysis of homopolyacrylonitrile. The acrylamino group increased as a function of hydrolysis time, while crystallinity decreased. Differential scanning calorimetry and a thermal gravimetric analysis indicated that the acylamino introduced by acidic hydrolysis effectively enhanced the cyclization reaction at low temperature due to the change of the cyclization reaction mechanism. Char-yield of AN-AM copolymers also gradually increased with increasing hydrolysis time. The maximum char-yield was 49.48% when hydrolized at $23^{\circ}C$ in 65% nitric acid solution for 18 h, which was 30% higher than that of non-acidic hydrolysis of homopolyacrylonitrile. Simulation of the practical process also showed an increase of char yields, where the char yields were 55.43% and 62.60% for homopolyacrylonitrile and copolyacrylonitrile, respectively, with a hydrolysis time of 13 h.

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References

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