Thermal and Electrical Properties of PS/MWCNT Composite Prepared by Solution Mixing: Effect of Surface Modification of MWCNT

Solution Mixing법에 의한 PS/MWCNT 복합재료의 열 및 전기전도 특성: MWCNT 표면 개질의 영향

  • Park, Eun-Ju (Department of Chemical Engineering, Inha University) ;
  • Lee, Jeong-Woo (Department of Chemical Engineering, Inha University) ;
  • Jung, Dong-Soo (Department of Mechanical Engineering, Inha University) ;
  • Shim, Sang-Eun (Department of Mechanical Engineering, Inha University)
  • Received : 2010.01.08
  • Accepted : 2010.01.19
  • Published : 2010.03.30

Abstract

Herein, the effect of the dispersion uniformity of the multi-wall carbon nanotube (MWCNT) on the thermal and electrical conductivity of polystyrene (PS)/MWCNT composite was investigated. The PS/MWCNT composites were prepared by solution mixing from dispersions of various MWCNTs in PS/tetrahydrofuran (THF) solution. Three types of MWCNTs were used; pristine MWCNT, hydroxyl functionalized MWCNT, which was functionalized with $KMnO_4$ in the presence of a phase transfer catalyst at room temperature, and pristine MWCNT with BYK-9077 as a dispersant. It was found that the stable dispersion state of MWCNT in PS/THF solutions significantly improved the thermal and electrical conductivity of the ultimate composites. It is noted that the thermal and electrical conductivity of PS/3 wt% pristine MWCNT composite with BYK-9077 were about 9.4 and 30~50% higher than those of PS/3 wt% pristine MWCNT composite, respectively.

본 논문에서는 MWCNT/PS 복합재료 제조 시, MWCNT의 표면 개질에 의한 분산도에 따른 열 및 전기전도도에 관하여 연구하였다. 다양한 종류의 MWCNT를 PS/THF 용액에서 분산시킨 후 침전을 통하여 복합재료를 제조하였다. 사용된 MWCNT는 pristine MWCNT의 상이동 촉매 존재 하에서 상온에서 $KMnO_4$를 이용하여 하이드록실기로 개질된 MWCNT, BYK-9077 분산제를 이용한 MWCNT를 사용하였다. 분석 결과 MWCNT의 PS/THF 용액 내에서의 분산 안정성은 최종 제조되어진 복합재료의 열 및 전기전도도 특성 향상에 중요하게 기여하였다. PS/3 wt% pristine MWCNT에 비하여, 특히 분산제 BYK-9077을 사용한 경우에는 열전도도가 9.7% 및 전기전도도가 30~50% 향상되는 결과를 얻었다.

Keywords

References

  1. M. Moniruzzaman and K.I. Winey, "Polymer nanocomposites containing carbon nanotubes", Macromolecules, 39, 5194 (2006). https://doi.org/10.1021/ma060733p
  2. P. Chen, H.S. Kim, and H.J. Jin, "Preparation, properties and application of polyamide/carbon nanotube nanocomposites", Macromol. Res., 17, 207 (2009). https://doi.org/10.1007/BF03218681
  3. D.S. Bang, H.S. Kye, U.R. Cho, B.G. Min, and K.C. Shin, "Elastomer nanocomposites(I)", Elastom. Compos., 44, 22 (2009).
  4. H.T. Ham, C.M. Koo, S.O. Kim, Y.S. Choi, and I.J. Chung, "Influence of oxyfluorination on physicochemical characteristics of carbon fibers and their reinforced epoxy composites", Macromol. Res., 12, 384 (2004). https://doi.org/10.1007/BF03218416
  5. E.T. Thostenson, C. Li, and T.W. Chou, "Nanocomposites in context", Compos. Sci. Technol., 65, 491 (2005). https://doi.org/10.1016/j.compscitech.2004.11.003
  6. H.S. Kim, B.H. Park, J.S. Yoon, and H.J. Jin, "Nylon 610/functionalized multiwalled carbon nanotubes composites by in situ interfacial polymerization", Mater. Lett., 61, 2251 (2007). https://doi.org/10.1016/j.matlet.2006.08.057
  7. N. Zhang, J. Xie, and V.K. Varadan, "Functionalization of carbon nanotubes by potassium permanganate assisted with phase transfer catalyst", Smart Mater. Struct., 11, 962 (2002). https://doi.org/10.1088/0964-1726/11/6/318
  8. L. Vaisman, H.D. Wagner, and G. Marom, "The role of surfactants in dispersion of carbon nanotubes", Adv. Colloid Interf. Sci., 128, 37 (2006). https://doi.org/10.1016/j.cis.2006.11.007
  9. J. Lee, M. Kim, C.K. Hong, and S.E. Shim, "Measurement of the dispersion stability of pristine and surface-modified multiwalled carbon nanotubes in various nonpolar and polar solvents", Meas. Sci. Technol., 18, 3707 (2007). https://doi.org/10.1088/0957-0233/18/12/005
  10. M.W. Marshall, S. Popa-Nita, and J.G. Shapter, "Measurement of functionalised carbon nanotube carboxylic acid groups using a simple chemical process", Carbon, 44, 1137 (2006). https://doi.org/10.1016/j.carbon.2005.11.010
  11. S. Hong, M. Kim, C.K. Hong, D. Jung, and S.E. Shim, "Encapsulation of multi-walled carbon nanotubes by poly(4- vinylpyridine) and its dispersion stability in various solvent media", Synthetic Met., 158, 900 (2008). https://doi.org/10.1016/j.synthmet.2008.06.023
  12. M. Kim, C.K. Hong, S. Choe, and S.E. Shim, "Synthesis of polystyrene brush on multiwalled carbon nanotubes treated with $KMnO_4$ in the presence of a phase-transfer catalyst", J. Polym. Sci. Part A: Polym. Chem., 45, 4413 (2007). https://doi.org/10.1002/pola.22190
  13. Y. Sasson and R. Neumann, Handbook of phase transfer catalysis, Chapman & Hall, London, UK (1997).
  14. D.G. Lee and V.S. Chang, "Polyethylene glycol as a phase transfer catalyst for aryldiazonium salt reactions", J. Org. Chem., 43, 1532 (1978). https://doi.org/10.1021/jo00402a009
  15. G. Wang, Z. Qu, L. Liu, Q. Shi, and J. Guo, "Study of SMA graft modified MWNT/PVC composite materials", Mater. Sci. Eng. A, 472, 136 (2008). https://doi.org/10.1016/j.msea.2007.03.017
  16. H. Meng, G.X. Sui, P.F. Fang, and R. Yang, "Effects of acidand diamine-modified MWNTs on the mechanical properties and crystallization behavior of polyamide 6", Polymer, 49, 610 (2008).
  17. M. Monthioux, B.W. Smith, B. Burteaux, A. Claye, J.E. Fischer, and D.E. Luzzi, "Sensitivity of single-wall carbon nanotubes to chemical processing: an electron microscopy investigation", Carbon, 39, 1251 (2001). https://doi.org/10.1016/S0008-6223(00)00249-9
  18. F.H. Ko, C.Y. Lee, C.J. Ko, and T.C. Chu, "Purification of multi-walled carbon nanotubes through microwave heating of nitric acid in a closed vessel", Carbon, 43, 727 (2005). https://doi.org/10.1016/j.carbon.2004.10.042
  19. Y. Li, Y. Liu, Y. Zuo, W. Chi, B. Liu, and Z. Shen, "Effects of dispersants on dispersion of carbon nanotubes and properties of fluorocarbon resin nanocomposites", J. Mater. Sci., 43, 3738 (2008). https://doi.org/10.1007/s10853-008-2617-y
  20. J.P. Smalla, L. Shib, and P. Kim, "Mesoscopic thermal and thermoelectric measurements of individual carbon nanotubes", Solid State. Commun., 127, 181 (2003) https://doi.org/10.1016/S0038-1098(03)00341-7
  21. S.T. Huxtable, D.G. Cahill, S. Shenogin, L.P. Xue, R. Ozisik, P. Barone, M. Usrey, M.S. Strano, G. Siddons, M. Shim, and P. Keblinski, "Interfacial heat flow in carbon nanotube suspensions", Nat. Mater., 2, 731 (2003). https://doi.org/10.1038/nmat996
  22. J. Brandrup, E.H. Immergut, E.A. Grulke, and D.R. Bloch, Polymer handbook, Wiley, New York (1999).