Epoxy - carbon nanotubes composites with improved thermal and

« Marie Skłodowska-Curie »
scientific award in the field of
materials science
Epoxy - carbon nanotubes composites with improved
thermal and electrical conductivity for CFRP application
Ewelina Ciecierska
Warsaw University of Technology, Faculty of Materials Science and Engineering
Woloska, 141, 02-507 Warsaw, Poland
Selection of mixing method and nanotubes type
1,00E+01
1- mechanical;
2,3- mechanical
+ultrasonic;
1,00E+00
s [S/m]
1,00E-01
4, 5- mechanical
+ultrasonic+
surfactant;
1,00E-02
6- three roll
milling
1,00E-03
1,00E-04
1,00E-05
1
1,00E+01
2
0,1-0,5 m
3
4
5
6
1,5 m
1 m
1,00E-01
1,00E-03
Conductivity [S/m]
Epoxy resin is the most often used resin in aircraft industry, due to
good properties such as low density, low shrinkage during curing,
high mechanical properties, and low absorption of water. The
biggest disadvantage of epoxy resin is low electrical and thermal
conductivity. Carbon nanotubes (CNTs) exhibit very unusual
properties, low density, high Young's modulus, high tensile
strength. They can conduct high density current, they are resistant
to high temperature, and have high thermal conductivity. They have
high surface area and even small amount of CNTs can significantly
change properties of the material. Development of epoxy/carbon
nanotubes composites can be meaningful if we think about new
application in aircraft structure for lightning strike protection,
electromagnetic interference shielding. Application of conductive
nanocomposites will reduce the weight of airplane and in the result
will diminish the fuel consumption. Electrical conductivity of polymer
fiber reinforced composites is still not enough. Increase of
conductivity of polymer fiber reinforced composites can be obtain
by increasing conductivity of resin. Conductivity of polymer
composites can be increased by adding metal powders or metal
fibers, but it leads to the increase of materials weight, which is
disadvantage in aircraft industry. In my work carbon nanotubes are
used as a filler.
Aim of my work is to improve conductivity of commonly used epoxy
resins and also to improve mechanical properties of materials. In
my PhD thesis different type of carbon nanotubes, modified and
non-modified were applied. For nanotubes dispersion in polymer
matrix numerous mixing methods were used. Influence of
application of solvents and surfactants on dispersion was also
evaluated. Impact of curing parameters on conductivity was also
measured. For manufactured sample electrical and thermal
conductivity was measured. Microscopy observations for dispersion
control were carried out. Basis on obtained results the best method
of mixing and type of nanotubes was selected.
Results of my PhD thesis formed the basis for the next project
„„Development of manufacturing technology of aviation composite
structures with carbon prepregs without autoclave process” where I
was taking part. One of the aims of these project was to improve
thermal conductivity of CFRP composites. To achive this goal
epoxy composites with 1 wt.% of CNTs were used. Such high filler
concentration does not let fiber impregantaion. For matrix dilutation
styrene was used. Influence of solvent addition on thermal
conductivity, rheology properties, gel time of epoxy resin was
investigated.
Results of my scientific work in the field of epoxy/carbon nanotubes
composites are papers in reptuable journals and also on patent
application (number P.411637- Composite materials and
manufacturing method of composite materials).
1,00E-05
1,00E-07
1,00E-09
1,00E-11
1,00E-13
1,00E-15
Epoxy
COOH 3% COOH 5% NH2 2-3% OH 4-5%
COOH
(Nc)
NH2 (Nc)
nonmodified
(Nc)
nonmodified
(Nc)
CFRP with carbon nanotubes
Scanning electron
microscopy images of
laminates with epoxy
matrix doped with
carbon nanotubes
fabricated:
a), b) without styrene,
c), d) with 15 mass %
of styrene
Glass transition
temperature
Tg /°C
Sample
Thermal diffusivity CFRP laminates
with epoxy/carbon nanotubes matrix
containing 1 mass% of CNTs diluted
with different amount of styrene
EP
EP+1%CNT
EP+1%CNT +5%styrene
EP+1%CNT +10%styrene
EP+1%CNT +15%styrene
157
167
155
100
100
Gel time dependently on styrene amount
1- E. Ciecierska, A. Boczkowska, M. Kubiś, P. Chabera, T. Wiśniewski, „Effect of styrene addition on thermal properties of epoxy resin doped with carbon nanotubes” – in review in Polymers for Advanced Technologies
2- E. Ciecierska, A. Boczkowska, K. J. Kurzydlowski, I.D. Rosca, S. V. Hoa, „The effect of carbon nanotubes on epoxy matrix nanocomposites”, Journal of Thermal Analysis and Calorimetry 111 (2), pp. 1019-1024
3- E. Ciecierska, A. Boczkowska, K. J. Kurzydlowski, „Characterization of polymer based nanocomposites with carbon nanotubes”, Journal of Nanoscience and Nanotechnology 14 (4), pp. 2690-2699
4- M. Wladyka-Przybylak, D. Wesolek, W. Gieparda, A. Boczkowska, E. Ciecierska, „Functionalization effect on physico-mechanical properties of multi-walled carbon nanotubes/epoxy composites”, Polymers for
Advanced Technologies 22, 1,pp 48–59
5- M. Wladyka-Przybylak, D. Wesolek, W. Gieparda, A. Boczkowska, E. Ciecierska, “The effect of the surface modification of carbon nanotubes on their dispersionin the epoxy matrix”, Polish Journal of Chemical
Technology, 13, 2, 62-69, 2011