Third Day Poster Session, 17 June 2010 - NanoTR-VI

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Poster Session, Thursday, June 17
Theme F686 - N1123
Preparation and SEM Characterization of Nanocomposites Based on HDPE and Graphite Powder
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M. SarkanatP P, UI. H. TavmanUP P*, K. SeverP P, A. TurgutP P, Y. SekiP P, P ErbayP P, F.GünerP Pand I.Özdemir P
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PMechanical Engineering Dept., Ege University, 35100 Bornova Izmir, Turkey
PMechanical Engineering Dept., Dokuz Eylul Univ., 35100 Bornova Izmir, Turkey
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PTDepartment of Chemistry, Dokuz Eylül University, Buca, 35160 zmir, Turkey
PPetkim Petrokimya Holding A.., 35801 Aliaa-zmir
PFaculty of Engineering, Bartin University, Bartin, Turkey
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Abstract-Polymers which are in general insulating materials, may be made electrically and thermally conductive by the addition
of conductive fillers such as graphite, carbon black, metal and metal oxide powders or fibers. In this study the conductive fillers
used were nanosized graphite particles, the base material was high density polyethylene (HDPE). Nanocomposites containing up
to 30 weight % of filler material were prepared by mixing them in a Brabender Plasticorder. SEM investigations of the
composites prepared have been performed.
Heat buildup in electronic components, lighting,
transformer housings, and other devices that produce
unwanted heat can limit service life and reduce operating
efficiency. Traditionally, metals which are good thermal
conductor, has been used for thermal management
equipment such as heat sinks and heat exchangers. But
metal parts are heavy and costly to produce. In recent
years, they are being replaced by injection molded or
extruded heat-conducting plastic compounds that provide
lightweight cooling solutions. Advantages include design
flexibility, parts consolidation, corrosion and chemical
resistance, reduction of secondary finishing operations,
and the processing benefits of plastics. Polymers which in
general have low thermal conductivities (0.1-0.5 W/m.K)
are made conductive by compounding conductive fillers
such as graphite fibers and ceramic particles. Some
thermally conductive plastics may offer up to 500 times (to
100 W/mK) the conductivity of base polymers. These
materials can be used to tailor the thermal conductivity to
individual applications, providing the ability to dissipate
heat precisely and efficiently.
Various fillers, including metallic powders, are used to
produce thermally conductive polymers. Graphite powders
or fibers are frequently used especially for an improvement
of electrical conductivity, antistatic properties as well as
thermal conductivity of plastics, [1], [2]. The recent
advancement of nano-scale compounding technique
enables the preparation of highly electrically conductive
polymeric nanocomposites with low loading of conductive
fillers. Nanocomposites may offer enhanced physical
features such as increased stiffness, strength, barrier
properties and heat resistance, without loss of impact
strength in a very broad range of common synthetic or
natural polymers. In this study the conductive filler was
graphite with an average particle size of 400 nm and purity
of 99.9%, the matrix material was high density
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polyethylene (HDPE) with a density of 0.968 g/ cmP a
melt index of 5.8 g/10 min, supplied by Petkim A..-
zmir. Nanocomposites containing up to 30 weight % of
graphite powder filler material were prepared by mixing
them in a Brabender Plasticorder at 180°C for 15 minutes.
The mixing chamber of the Brabender apparatus was then
opened and the resulting mixture is taken out, then after
passing through the rollers the mixture was solidified. The
resultant mixture in then put in a compression molding die
and compressed in a compression molding press at 180°C,
under 40 kP pressure for five minutes to obtain samples in
the form of sheets of 1mm in thickness.
SEM micrographs of graphite–HDPE composites are
shown in Figure 1. It can be seen that the graphite powder
are dispersed uniformly in the matrix as seen in figure 1.
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Figure 1. SEM micrographs of Graphite reinforced HDPE
composites a) %4 by weight Graphite reinforced HDPE, b) %10
by weight Graphite reinforced HDPE, c) %20 by weight Graphite
reinforced HDPE
This research was supported by the Scientific Support of
the bilateral Project No. 107M227 of TUBITAK and SAS
and partly by the project VEGA No. 2/0063/09.
* corresponding author: HTismail.tavman@deu.edu.trT
[1] Krupa,I., Chodák,I., 200, Physical Properties of thermoplastic/
graphite composites, Eur. Polym. J., 37(11) 2159-2168.
[2] Krupa,I., Novak,I., Chodák,I., 2004, HTElectrically and
thermally conductive polyethylene/graphite composites and their
mechanical propertiesTH, Synthetic Metals, 145, 245-252.
6th Nanoscience and Nanotechnology Conference, zmir, 2010 739