Hostname: page-component-76fb5796d-x4r87 Total loading time: 0 Render date: 2024-04-25T07:57:17.118Z Has data issue: false hasContentIssue false

iPP/CNTs Multifunctional Polymer Nanocomposite

Published online by Cambridge University Press:  22 February 2012

Parvathalu Kalakonda
Affiliation:
Department of Physics, WPI, Worcester, MA 01609, U.S.A.
Sabyasachi Sarkar
Affiliation:
Department of Physics, WPI, Worcester, MA 01609, U.S.A.
Erin A. Gombos
Affiliation:
Department of Natural Sciences, Assumption College, Worcester, MA 01609, U.S.A.
Georgi Yordanov Georgiev*
Affiliation:
Department of Natural Sciences, Assumption College, Worcester, MA 01609, U.S.A. Department of Physics and Astronomy, Tufts University, Medford, MA 02155, U.S.A.
Germano Iannacchione
Affiliation:
Department of Physics, WPI, Worcester, MA 01609, U.S.A.
Peggy Cebe
Affiliation:
Department of Physics and Astronomy, Tufts University, Medford, MA 02155, U.S.A.
*
*indicates corresponding author: ggeorgie@assumption.edu; georgi@alumni.tufts.edu
Get access

Abstract

We present a hybrid structure of Isotactic Polypropylene (iPP) nanocomposite with multiwall carbon nanotubes (MWCNTs). The polymer component contributes to the optical properties, flexibility and integrity of the polymer film while the carbon nanotubes change the thermal and mechanical stability, electrical and thermal conductivity and sensitivity. The multifunctional characteristics of this nanocomposite material are enhanced by anisotropic organization of the nanotubes and polymer through melt shearing which provides organization of the structural constituents at the molecular, nano, and micro length scales. This results in anisotropy of the macroscopic composite film properties parallel and perpendicular to the direction of shearing. On the molecular scale, the CNTs control the arrangement of the polymer molecules in a crystal lattice. On the nanometer scale, the CNTs couple to and align with the smectic normal of the liquid crystal phase of iPP. On the micron scale and larger, the secondary polymer crystal structure is rearranged due to the pinning of the polymer at the CNT surface to form fibrillar rather than spherulitic structures. These multi-scale rearrangements affect the optical, thermal, electrical, mechanical and chemical properties of the nanocomposite film. Our findings indicate that the CNTs under shear induce a novel anisotropy to the various thermo-physical properties of the iPP/CNTs films. We introduce an approach to extract the shear induced orientational order from the thermal conductivity of the dispersed CNTs. The index of refraction of the nanocomposites was also estimated via ellipsometry and was found to decrease slightly when CNTs were added and also showed shear induced anisotropy. The comparison between the results from the different experiments methods for probing induced anisotropy by melt shearing shows that orientation in iPP/CNTs nanocomposites induces anisotropy in multiple macroscopic properties.

Type
Research Article
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Georgiev, G., McIntyre, M. B., Judith, R., Gombos, E. A. and Cebe, P., in Symposium Artificially Induced Crystalline Alignment in Thin Films and Nanostructures (Cambridge Journals Online, Cambridge University Press, UK, Materials Research Society Symposium Proceeding, 1308, Warrendale, PA, 2011), DD0709, DOI:10.1557/opl.2011.157, mrsf10-1308-dd07-09 Google Scholar
2. Song, W., Kinloch, I.A., Windle, A.H., Science 302, 1363 (2003).Google Scholar
3. Dawid, A., Gwizdała, W., Journal of Non-Crystalline Solids 355, 13021306 (2009).Google Scholar
4. Gwizdała, W., Górny, K., Gburski, Z., Journal of Molecular Structure 887, 148151 (2008).Google Scholar
5. Georgiev, G., Gombos, E. A., McIntyre, M., Mattera, M., Gati, P., Cabrera, Y. and Cebe, P., in Nanoscale Pattern Formation, edited by Chason, E., Cuerno, R., Gray, J., Heinig, K.-H., (Mater. Res. Soc. Symp. Proc. 1228E, Warrendale, PA, 2010), KK1181.Google Scholar
6. Kalakonda, P., Gombos, E. A., Georgiev, G. Y., Iannacchione, G.S. and Cebe, P., in Transport Properties in Polymer Nanocomposites II, Annual meeting of the Materials Research Society, (Boston, Dec. 2011) Paper# DD4.1; Control ID: 1130077 submitted Google Scholar
7. Sarkar, S., Kalakonda, P., Georgiev, G.Y., Iannacchione, G.S. and Cebe, P., in Transport Properties in Polymer Nanocomposites II, Annual meeting of the Materials Research Society, (Boston, Dec.2011) Paper# DD4.2; Control ID: 1158918. Submitted Google Scholar
8. Kalakonda, P., Gombos, E. A., Hoonjan, G. S., Georgiev, G.Y., Iannacchione, G. S. and Cebe, P., in Transport Properties in Polymer Nanocomposites II, Annual meeting of the Materials Research Society, (Boston, Dec. 2011) Paper# DD1.1; Control ID: 1130053 submitted Google Scholar