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Dielectric properties of dielectrophoretically assembled particulate-polymer composites

Published online by Cambridge University Press:  31 January 2011

C. P. Bowen
Affiliation:
Intercollege Materials Research Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
R. E. Newnham
Affiliation:
Intercollege Materials Research Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
C. A. Randall
Affiliation:
Intercollege Materials Research Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
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The dielectrophoretic effect is a phenomenon in which dipole-dipole interactions are induced between particles in a suspension by an electric field.1−5 This dipole interaction leads to the formation of chains or fibrils parallel to the applied electric field. Recently, the dielectrophoretic effect has been shown to be a possible composite assembly technique permitting property changes to be induced with the appropriate electric fields.6,7 The results presented in this paper show that the dielectrophoretic assembly process can be used to engineer anisotropy into composite materials. Various filler materials are aligned in a thermoset polyurethane matrix and the dielectric properties are measured. Comparisons are drawn between the dielectrophoretically assembled composites and those processed conventionally in the absence of an electric field. Dielectric properties are modeled with modified mixing laws and discussed in relation to the composite microstructure and the alpha relaxations of the polymer phase.

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Articles
Copyright
Copyright © Materials Research Society 1998

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References

1.Pohl, H. A., Dielectrophoresis: The Behavior of Neutral Matter in Non-Uniform Electric Fields (Cambridge University Press, Cambridge, London, and New York, 1978).Google Scholar
2.Block, H., Kelly, J. P., Qiu, A., and Watson, T., Langmuir 6, 614 (1990).CrossRefGoogle Scholar
3.Halsey, T. C., Science 258, 761764 (1992).CrossRefGoogle Scholar
4.Davis, L. C., J. Appl. Phys. 72, 1334 (1992).CrossRefGoogle Scholar
5.Anderson, R. A., Langmuir 10, 29172928 (1994).CrossRefGoogle Scholar
6.Randall, C. A., Miller, D. V., Adair, J. H., and Bhalla, A. S., J. Mater. Res. 8, 899904 (1993).CrossRefGoogle Scholar
7.Bowen, C. P., Shrout, T. R., Newnham, R. E., and Randall, C. A., J. Int. Mater. Syst. Struct. 6 (2), 159 (1995).CrossRefGoogle Scholar
8.Bowen, C. P., Van Tassel, J., Matsko, M., and Randall, C. A., ISAF ‘96, Rutgers, New Jersey.Google Scholar
9.Sarkar, P. and Nicholson, P., J. Am. Ceram. Soc. 79 (8), 19872002 (1996).CrossRefGoogle Scholar
10.Newnham, R. E., Skinner, D. P., and Cross, L. E., Mater. Res. Bull. 13, 525 (1978).CrossRefGoogle Scholar
11.Bowen, C. P., Bhalla, A. S., Newnham, R. E., and Randall, C. A., J. Mater. Res. 9, 781788 (1994).CrossRefGoogle Scholar
12.Yoshikawa, S., Selvaraj, U., Moses, P., Witham, J., Meyers, R., and Shrout, T. R., J. Int. Mater. Syst. Struct. 6 (2), 152 (1995).CrossRefGoogle Scholar
13.Roande, E. and Saiz, E., Dipole Moments and Birefringence of Polymers (Prentice-Hall, Englewood Cliffs, NJ, 1992).Google Scholar
14.Jonscher, A. K., Dielectric Relaxations in Solids (Chelsea Dielectrics Press, London, 1983).Google Scholar
15.Jonscher, A. K., IEEE Electrical Insulation Mag. 6 (3), 24 (1990).CrossRefGoogle Scholar
16.Maxwell, J. C., A Treatise on Electricity and Magnetism (Dover Publishing Co, New York, 1954).Google Scholar