Abstract
In this research, the thermal diffusivity of composites based on ethylene- vinyl acetate (EVA) copolymer filled with two kinds of reinforcement graphite materials was investigated. The reinforcement graphite fillers were untreated natural graphite (UG) and expanded graphite (EG). Composite samples up to 29.3 % graphite particle volumetric concentrations (50 % mass concentration) were prepared by the melt- mixing process in a Brabender Plasticorder. Upon mixing, the EG exfoliates in these films having nanosized thicknesses as evidenced by TEM micrographs. Thus, the thermal diffusivity and electrical conductivity of composites based on the ethylene-vinyl acetate matrix filled with nanostructuralized expanded graphite and standard, micro-sized graphite were investigated. From the experimental results it was deduced that the electrical conductivity was not only a function of filler concentration, but also strongly dependent on the graphite structure. The percolation concentration of the filler was found to be (15 to 17) vol% for micro-sized natural graphite, whereas the percolation concentration of the filler in nanocomposites filled with expanded graphite was much lower, about (5 to 6) vol%. The electrical conductivity of nanocomposites was also much higher than the electrical conductivity of composites filled with micro-sized filler at similar concentrations. Similarly, the values of the thermal diffusivity for the nanocomposites, EG-filled EVA, were significantly higher than the thermal diffusivity of the composites filled with micro-sized filler, UG-filled EVA, at similar concentrations. For 29.3 % graphite particle volumetric concentrations, the thermal diffusivity was 8.23 × 10−7 m2 · s−1 for EG-filled EVA and 6.14 × 10−7 m2 · s−1 for UG-filled EVA. The thermal diffusivity was measured by the flash method.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Fu S.Y., Feng X.Q., Lauke B., Mai Y.W.: Compos. Part B 39, 933 (2008)
Drzal L.T., Fukushima H.: Polym. Prepr. 42, 42 (2001)
Viculis L.M., Mack J.J., Kaner R.B.: Science 299, 1361 (2003)
Chen G., Wu C., Weng W., Wu D., Yan W.: Polymer 44, 1781 (2003)
Chen G., Weng W., Wu D., Wu C., Lu J., Wang P., Chen X.: Carbon 42, 753 (2004)
Sheng W., Wong S.C.: Compos. Sci. Technol. 63, 225 (2003)
Zheng W., Wong S.C., Sue H.J.: Polymer 73, 6767 (2002)
Pan Y.X., Yu Z.Z., Ou Y.C., Hu G.H.: J. Polym. Sci., Part B 38, 1626 (2000)
J.W. Shen, X.M. Chen, W.Y. Huang, J. App. Polym. Sci. 88, 1864 (2003)
Parker W., Jenkins R., Buttler C., Abott G.: J. Appl. Phys. 32, 1679 (1961)
Cowan R.D.: J. Appl. Phys. 34, 926 (1963)
Beedham K., Dalrymple L.P.: Rev. Int. Hautes Temp. Refract. 7, 278 (1970)
Donaldson A.B.: J. Appl. Phys. 43, 4226 (1972)
Clark L.M. III, Taylor R.E.: J. Appl. Phys. 46, 714 (1975)
Degiovanni A.: Int. J. Heat Mass Transf. 30, 2199 (1987)
Cape J., Lehman G.: J. Appl. Phys. 34, 1909 (1963)
Lechner T., Hahne E.: Thermochim. Acta 218, 341 (1993)
Clark L.M. III, Taylor R.: J. Appl. Phys. 46, 714 (1975)
Baba T., Ono A.: Meas. Sci. Technol. 12, 2046 (2001)
van der Pauw L.J.: Philips Res. Rep. 13, 1 (1958)
de Souza F.G., Soares B.G., Pinto J.C.: Eur. Polym. J. 44, 3908 (2008)
Svoboda P., Theravalappil R., Poongavalappil S., Vilcakova J., Svobodova D., Mokrejs P., Blaha A.: Polym. Eng. Sci. 52, 1241 (2012)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Tavman, I.H., Turgut, A., da Fonseca, H.M. et al. Thermal-Diffusivity Measurements of Conductive Composites Based on EVA Copolymer Filled With Expanded and Unexpanded Graphite. Int J Thermophys 34, 2297–2306 (2013). https://doi.org/10.1007/s10765-012-1231-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10765-012-1231-z