Korea-Australia Rheology Journal

The Korean Society of Rheology (한국유변학회)
권호 표지

Development of polypropylene-clay nanocomposite with supercritical $CO_2$ assisted twin screw extrusion

  • Hwang, Tae-Yong (Department of Chemical and Biomolecular Engineering, Sogang University) ;
  • Lee, Sang-Myung (LG Micron Ltd.) ;
  • Ahn, Young-Joon (Department of Chemical and Biomolecular Engineering, Sogang University) ;
  • Lee, Jae-Wook (Department of Chemical and Biomolecular Engineering, Sogang University)
  • Published : 2008.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

The aim of this study is to explore the possibility of incorporating supercritical carbon dioxide ($scCO_2$) into twin screw extrusion process for the production of polypropylene-clay nanocomposite (PPCN). The $CO_2$ is used as a reversible plasticizer which is expected to rapidly transport polymeric chains into the galleries of clay layers in its supercritical condition inside the extruder barrel and to expand the gallery spacings in its sub-critical state upon emerging from die. The structure and properties of the resulting PPCNs are characterized using wide-angle X-ray diffraction (WAXD), transmission electron microscopy (TEM), rheometry, thermogravimetry and mechanical testing. In the processing of the PPCNs with $scCO_2$, optimum $scCO_2$ concentration and screw speed which maximized the degree of intercalation of clay layers were observed. The WAXD result reveals that the PP/PP-g-MA/clay system treated with $scCO_2$ has more exfoliated structure than that without $scCO_2$ treatment, which is supported by TEM result. $scCO_2$ processing enhanced the thermal stability of PPCN hybrids. From the measurement of linear viscoelastic property, a solid-like behavior at low frequency was observed for the PPCNs with high concentration of PP-g-MA. The use of $scCO_2$ generally increased Young's modulus and tensile strength of PPCN hybrids.

Keywords

References

  1. Brennecke, J. F., 1997, Solvents: molecular trees for green chemistry, Nature 389, 333-334 https://doi.org/10.1038/38611
  2. Davis, C. H., L. J. Mathias, J. W. Gilman, D. A. Schiraldi, J. R. Shields, P. Trulove, T. E. Sutto and H. C. Delong, 2002, Effects of melt-processing conditions on the quality of poly(ethylene terephthalate) montmorillonite clay nanocomposites, J. Polym. Sci., Part B: Polym. Phys. 40, 2661-2666 https://doi.org/10.1002/polb.10331
  3. Fischer, H. R. and L. H. Gielgens, 1999, Nanocomposites from polymers and layered minerals, Acta Polymerica 50, 122-126 https://doi.org/10.1002/(SICI)1521-4044(19990401)50:4<122::AID-APOL122>3.0.CO;2-X
  4. Galgali, G., C. Ramesh and A. Lele, 2001, A rheological study on the kinetics of hybrid formation in polypropylene nanocomposites, Macromolecules 34, 852-858 https://doi.org/10.1021/ma000565f
  5. Garcia-Leiner, M. A., 2004, Solid and melt state processing of polymers and their composites in supercritical carbon dioxide, Ph.D. Dissertation, University of Massachusetts, Amherst, MA
  6. Giannelis, E. P., 1996, Polymer layered silicate nanocomposites, Adv. Mater. 8, 29-35 https://doi.org/10.1002/adma.19960080104
  7. Gilnian, J. W., T. C. L. Kashivagi, E. P. Giannelis, E. Manias, S. Lomakin, J. D. Lichtenhan, et al. In: M. Le Bras, G. Caniino, S. Bourbigot, R. Delobel, editors. 1998, Fire retardancy of polymers. Cambridge: The Royal Society of Chemistry
  8. Ke, Y. C., C. Long, and Z. Qi, 1999, Crystallization, properties, and crystal and nanoscale morphology of PET-clay nanocomposites, J. Appl. Polym. Sci. 71, 1139-1146 https://doi.org/10.1002/(SICI)1097-4628(19990214)71:7<1139::AID-APP12>3.0.CO;2-E
  9. Kojima, Y. A., Usuki, M. Kawasumi, Y. Fukushima, A. Okada, T. Kurauchi and O. Kamigaito, 1993, Synthesis of nylon 6-clay hybrid, J. Mater. Res. 8, 1179-1184 https://doi.org/10.1557/JMR.1993.1179
  10. Jimenez, G., N. Ogata, H. Kawai and T. Ogihara, 1997, Structure and thermal/mechanical properties of poly (${\varepsilon}-caprolactone$)- clay blend, J. Appl. Polym. Sci. 64, 2211-2220 https://doi.org/10.1002/(SICI)1097-4628(19970613)64:11<2211::AID-APP17>3.0.CO;2-6
  11. Lan, T., P. D. Kaviratna and T. J. Pinnavaia, 1995, Mechanism of clay tactoid exfoliation in epoxy-clay nanocomposites, Chem. Mater. 7, 2144-2150 https://doi.org/10.1021/cm00059a023
  12. Manke, C. W., E. Gulari, D. F. Mielewski and E. C. C. Lee, 2002, System and method of delaminating a layered silicate material by supercritical fluid treatment, U.S. Pat. 6,469,073 B1
  13. Mark, J. E., 1996, Ceramic-reinforced polymers and polymermodified ceramics, Polym. Eng. Sci. 36, 2905-2920 https://doi.org/10.1002/pen.10692
  14. Messersmith, P. B. and E. P. Giannelis, 1994, Synthesis and characterization of layered silicate-epoxy nanocomposites, Chem. Mater. 6, 1719-1725 https://doi.org/10.1021/cm00046a026
  15. Messersmith, P. B. and E. P. Giannelis, 1995, Synthesis and barrier properties of poly($\varepsilon$-caprolactone)-layered silicate nanocomposites, J. Polym. Sci., Part A: Polym. Chem. 33, 1047-1057 https://doi.org/10.1002/pola.1995.080330707
  16. Mielewski, D. F., E. C. C. Lee, C. W. Manke and E. Gulari, 2002, System and method of preparing a reinforced polymer by supercritical fluid treatment, U.S. Pat. 6,753,360 B2
  17. Novak, B. M., 1993, Hybrid nanocomposite materials - between inorganic glasses and organic polymers, Adv. Mater. 5, 422-433 https://doi.org/10.1002/adma.19930050603
  18. Ogawa, M. and K. Kuroda, 1997, Preparation of inorganicorganic nanocomposites through intercalation of organoammonium ions into layered silicates, Bull. Chem. Soc. Jpn. 70, 2593-2618 https://doi.org/10.1246/bcsj.70.2593
  19. Okada, A. and A. Usuki, 1995, The chemistry of polymer-clay hybrids, Mater. Sci. Eng. C3, 109-115
  20. Schmidt, H., 1985, New type of non-crystalline solids between inorganic and organic materials, J. Non-Cryst. Solids 73, 681-691 https://doi.org/10.1016/0022-3093(85)90388-6
  21. Solomon, M. J., A. S. Almusallam, K. F. Seefeldt, A. Somwangthanaroj and P. Varadan, 2001, Rheology of polypropylene/ clay hybrid materials, Macromolecules 34, 1864-1872 https://doi.org/10.1021/ma001122e
  22. Treece, M. A. and J. P. Oberhauser, 2007, Processing of polypropylene- clay nanocomposites: Single-screw extrusion with inline supercritical carbon dioxide feed versus twin-screw extrusion, J. Appl. Polym. Sci. 103, 884-892 https://doi.org/10.1002/app.25226
  23. Usuki, A., M. Kato, A. Okata and T. Kurauchi, 1997, Synthesis of polypropylene-clay hybrid, J. Appl. Polym. Sci. 63, 137-139 https://doi.org/10.1002/(SICI)1097-4628(19970103)63:1<137::AID-APP15>3.0.CO;2-2
  24. Vaia, R. A., H. Ishii and E. P. Giannelis, 1993, Synthesis and properties of two-dimensional nanostructures by direct intercalation of polymer melts in layered silicates, Chem. Mater. 5, 1694-1696 https://doi.org/10.1021/cm00036a004
  25. Xu, L., S. Reeder, M. Thopasridharan, J. Ren, D. A. Shipp and R. Krishnamoorti, 2005, Structure and melt rheology of polystyrene- based layered silicate nanocomposites, Nanotechnology 16(7), 514-521 https://doi.org/10.1088/0957-4484/16/7/028
  26. Zax, D. B., D.-K. Yang, R. A. Santos, H. Hegemann, E. P. Giannelis and E. Manias, 2000, Dynamical heterogeneity in nanoconfined poly(styrene) chains, J. Chem. Phys. 112(6), 2945-2951 https://doi.org/10.1063/1.480867