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Carbon Nanotubes Induced Changes in the Phase Diagram and Crystal Structure of 5CB Liquid Crystal

Published online by Cambridge University Press:  24 May 2011

Georgi Y. 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.
Michael B. McIntyre
Affiliation:
Department of Natural Sciences, Assumption College, Worcester, MA 01609, U.S.A.
Erin A. Gombos
Affiliation:
Department of Natural Sciences, Assumption College, Worcester, MA 01609, U.S.A.
Peggy Cebe
Affiliation:
Department of Physics and Astronomy, Tufts University, Medford, MA 02155, U.S.A.
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Abstract

Multiwall Carbon Nanotubes (MWCNTs) form a nematic liquid crystalline (LC) phase in their lyotropic form, enabling their mixing and coupling of their director to that of nematic LCs. An important aspect of this LC/MWCNT interaction, for applications other than display technology, is looking at the ways the MWCNTs affect the physical properties of the LCs. We study the effect of MWCNTs on the nematic to crystal (N-C) phase transition of 4-cyano-4-npentylbiphenyl (5CB). Our Differential Scanning Calorimetry (DSC) results show a dramatic increase in N-C phase transition temperature of 14°C for only 0.1% and of 20°C for 1% MWCNT, due to the crystal nucleation activity of the nanotubes. Using Polarized Microscopy we observe a change in the crystalline order of 5CB from spherulitic at 0% MWCNTs to a multidomain in presence of MWCNTs. The new crystals resemble those formed by a smectic LC 4- Decyloxybenzoic acid. This is in line with predictions from simulations, that the MWCNTs form smectic order in nematic 5CB at their interface. MWCNTs induced modifications of the crystal phase of 5CB promise to create controlled novel crystal forms for the purposes of optical transmission and other applications.

Type
Research Article
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1. Eletskii, A., Physics - Uspekhi 50(3) 225261 (2007).Google Scholar
2. Baik, I., Jeon, S., and Lee, S., Park, K., Jeong, S., An, K. and Lee, Y., Applied Physics Letters 87 263110 (2005).Google Scholar
3. Basu, R., Sigdel, K. and Iannacchione, G., arXiv:0905.2779 (2009).Google Scholar
4. Dierking, I., Scalia, G. and Morales, P., J. Appl. Phys. 92, 8 (2004).Google Scholar
5. Duran, H., Gazdecki, B., Yamashita, A., Kyu, T., Liquid Crystals 32(7) 815821 (2005).Google Scholar
6. 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
7. Georgiev, G., Gombos, E. A., McIntyre, M. and Cebe, P., submitted to Liquid Crystal Materials - Beyond Displays (Mater. Res. Soc. Symp. Proc. Fall 2010 meeting in Boston, MA), ID: 910556Google Scholar
8. Dawid, A., Gwizdała, W., Journal of Non-Crystalline Solids 355 13021306 (2009)Google Scholar
9. Gwizdała, W., Górny, K., Gburski, Z., Journal of Molecular Structure 887 148151 (2008)Google Scholar
10. Lagerwall, J., and Scalia, G., Journal of Material Chemistry 18, 28902898 (2008)Google Scholar
11. Georgiev, G., Cabrera, Y., Wielgus, L., Iftikhar, Z., Mattera, M., Gati, P., Potter, A. and Cebe, P., in Artificially Induced Grain Alignment in Thin Films, edited by Matias, V., Hammond, R., Moon, S.-H., Hühne, R. (Mater. Res. Soc. Symp. Proc. 1150, Warrendale, PA, 2009), RR04-16, p. 185190 Google Scholar