Preparation and Gas Barrier Properties of Chitosan/Clay Nanocomposite Film

Chitosan/Clay 나노복합재료 필름의 제조와 기체투과 특성

  • Nam Sang Yong (Department of Polymer Science and Engineering, Engineering Research Institute, Gyeongsang National University) ;
  • Park Ji Soon (Department of Polymer Science and Engineering, Engineering Research Institute, Gyeongsang National University) ;
  • Rhim Ji Won (Department of Chemical Engineering, Hannam University) ;
  • Park Byung Gil (School of Chemical Engineering, College of Engineering, Hanyang University) ;
  • Kong Sung-Ho (School of Chemical Engineering, College of Engineering, Hanyang University)
  • 남상용 (경상대학교 고분자공학과) ;
  • 박지순 (경상대학교 고분자공학과) ;
  • 임지원 (한남대학교 화학공학과) ;
  • 박병길 (한양대학교 응용화학공학부) ;
  • 공성호 (한양대학교 응용화학공학부)
  • Published : 2005.09.01

Abstract

Chitosan film has potential applications in agriculture, food, and pharmacy. However, films made only from chitosan lack gas barrier and have poor mechanical properties. For enhanced gas barrier and mechanical properties, chitosan/clay nanocomposites have been prepared with montmorillonite (MMT) which is a layered structure of clays and chitosan. The cationic biopolymer, chitosan is intercalated into $Na^+-montmorillonite$ through cationic exchange and hydrogen bonding process. Diluted acetic acid is used as solvent f3r dissolving and dispersing chitosan. Chitosan was intercalated or exfoliated in MMT and it was confirmed by X-ray diffraction method. D-spacing of the characteristic peak from MMT plate in chitosan/clay nanocomposites was moved and diminished. The thermal stability and the mechanical properties of the nanocomposites are measured by TGA and Universal Testing Machine. Gas permeability through the chitosan/clay nanocomposites films decreased due to increased tortuosity made by intercalation of clay in chitosan.

키토산 필름은 농업, 식품과 제약 분야에서 응용이 가능하다. 그러나 키토산으로만 만들어진 필름은 기체투과성이 높고 기계적 물성에 약하다. 따라서 본 연구에서는 기체 투과성을 낮추고 기계적 물성을 높이기 위해 층상구조를 갖는 점토광물의 일종인 montorillonite (MMT)와 양이온 생체고분자인 키토산을 이용하여 양이온 교환과 수소결합과정을 통해 $Na^+-MMT$에 키토산을 삽입하여 키토산/Clay 나노복합재료를 제조하였다. 키토산/clay 나노 복합재료의 X-ray 회절패턴에서 $2\theta=7.5^{\circ}$에서 MMT의 basal reflection이 나타났고, $2\theta=3\~5^{\circ}$ 주위에서의 새로운 약하고 넓은 peak로서 더 낮은 각에서 MMT의 basal reflection의 이동에 의해 삽입된 나노 구조의 형성을 증명하였다. 또한 TGA thermogram를 이용하여 clay의 함유량이 증가할수록 제조된 나노복합재료의 열분해가 일어나는 범위의 질량감소가 줄어드는 것을 확인하므로서 내열성을 관찰하였다. 기계적 물성 성질을 측정하여 clay 함유량의 증가에 따른 인장 강도와 인장 모듈러스의 변화를 관찰하고, 키토산이 층상 실리케이트 내에 삽입하여 제조된 나노복합재료에서 clay의 함유량이 증가할수록 질소 투과경로의 tortuosity를 증가시켜서 기체 투과도를 감소시키는 것도 확인하였다.

Keywords

References

  1. S. F. Wang, L. Shen, Y. J. Tong, L. Chen, I. Y. Phang, P. Q. Lim, and T. X. Liu, 'Biopolymer chitosan/montmoriilonite nanocomposites: Preparation and characterization', Polymer Degradation and Stability (2005)
  2. S. S. Ray, K. Yamada, M. Okamoto, and K. Deda, 'New polylactide-layered silicate nanocomposites. 2. Concurrent improvements of material properties, biodegradability and melt rheology', Polymer., 44, 857 (2003)
  3. S. S. Ray, K. Yamada, M. Okamoto, Y. Fujimoto, A. Ogami, and K. Ueda, 'New polylactide/layered silicate nanocomposites. 5. Designing of materials with desired properties', Polymer., 44, 6633 (2003)
  4. C. M. Koo, M. J. Kim, M. H. Choi, S. O. Kim, and I. J. Chung, 'The effect of molecular weight of PP-g-MA/Layered silicate the nanocomposites', Hwahak Konghak., 39, 635 (2001)
  5. C. M. Koo, M. J Kim, M. H. Choi, S. O. Kim, and I. J. Chung, 'Study on the preparation and the properties of PP-g-MA/Layered silicate nanocomposites', Hwahak Konghak, 38, 691 (2001)
  6. M. W. Cho and Y. W. Chang, 'Synthesis and physical properties of polyurethane/clay nanocomposites', J. Korean Ind. Eng. Chem., 11, 517 (2000)
  7. Y. X. Xu, K. M. Kim, M. A. Hanna, and D. Nag, 'Citosan-starch composite film: preparation and characterization', Industrial Crops and Products, 21, 185 (2005)
  8. P. C. Lebaron, Z. Wang, and T. J. Pinnavaia, 'Polymer-layered silicate nanocomposites: an overview', Applied Clay Science, 15, 11 (1999)
  9. H. S. Goo, I. H. Kim, D. S. Joo, J. S. Park, J. H. Kim, and S. Y. Nam, 'Preparation and properties of Ionomer-Clay Hybrid Gas barrier Membranes', Membrane Journal., 14, 320 (2004)
  10. T. W. Son 'and G. S. Lee, 'Chitosan-electrolyte complex', Polymer science and Technology, 15, 335 (2004)
  11. X. Qu, A. Wirsen and A.-C. Albertsson, 'Effect of lactic/glycolic acid side chains on the thermal degradation kinetics of chitosan derivatives', Polymer., 41, 4841 (2000)
  12. F. Asira, Adv Chitin Sci., 46, 1 (2000)
  13. M. Darder, M. Colilla, and E. Ruiz-Hitzky, 'Biopolymer-clay mamocomposites based on chitosan intercalated in montmorillonite', Chem Mater., 15, 3774 (2003)
  14. C. Breen, 'The characterization and use of polycation-exchanged bentonites', Applied Clay Science, 15, 187 (1999)
  15. P. B. Messersmith and E. P. Giannelis, 'Synthesis and barrier properties of poly($\varepsilon$-caprolactone)layered silicate nanocommposites', J. Polym. Sci., Par A: Polym. Cem., 33, 1047 (1994)
  16. H. P. Klug and L. E. Alexander, 'X-ray diffraction procedures', 2nd ed., pp. 966, John Wiley and Sons, New York, NY (1974)
  17. P. H. Nadeau, J. M. Tait, W. J. McHardy, and M. J. Wilson, 'Interstratified X-ray diffraction characteristics of physical mixtures of elementary clay particles', Clay Minerals, 19, 67 (1984)
  18. S. F. Wang, Y. Hu, L. Song, Z. Z. Wang, Z. Y. Cheng, and W. C. Fan, 'Preparation and thermal properties of ABS/montmorillonite nanocomposite', Polymer Degradation and Stability, 77, 423 (2002)
  19. J. W. Gilman, 'Flammability and thermal stability studies of polymer layered-silicate (clay) nanocomposites', Applied Caly Science, 15, 31 (1999)
  20. R. A. Vaia, G. Price, P. N. Ruth, H. Y. Nguyen, and J. Lichtenhan, 'Polymer/layered silicate nanocomposites as high performance ablative materials', Applied Clay Science, 15, 67 (1999)
  21. S. S. Ray and M. Okamoto, 'Polymer/layered silicate nanocomposites: a review from preparation to processing', Prog. Polym. Sci., 28, 1539 (2003) https://doi.org/10.1016/S0079-6700(02)00115-6
  22. A. A. Gusev, H. R. Lusti, 'Rational Design of Nanocomposites for Barrier Applications', Advanced Materials, 13, 1641 (2001)
  23. B. Y., Yeom, B. R. Min, Y. J. Kim, and S. Y. Nam, 'Preparation and properties of SEBS (Styrene Ethylene Butadiene Styrene Copolymer)-Clay Hybrid Gas Barrier Membranes', Membrane Journal, 15, 62 (2005)