To effectively design polymer nanocomposites for industrial applications, it is necessary to understand the effects of nanoparticles on final proprieties of the polymers. In this project, systematic studies are carried out on the variability of the structural and mechanical properties as function of the different used nanofiller. Furthermore, the overall mission is to find a correlation between the structural and mechanical changes with the tribological proprieties of thermoplastic nanocomposite due to the inclusion of nanoparticle. This will allow to design nanocomposite materials by selecting ad hoc nanofillers in order to increase their efficiency for mechanical engineering and metal replacement applications.

1. NANOTECHITALY2012
High Performance Nanocomposites for Mechanical Application: Design, Preparation and
Characterization
A. Passalacqua (1), A. Ballestrazzi (2), S. Benuzzi (2), S. Valeri (2,3), J. M. Kenny (4), L. Torre (4), A. Iannoni (4), A.
Terenzi (4)
(1) Centro Interdipartimentale InterMech-MO.RE, University of Modena e Reggio Emilia, Via Vignolese 905/b - 41125
Modena, Italy
(2) Department of Physics, University di Modena e Reggio Emilia, Via Campi 213/A, 41125 Modena, Italy
(3) CNR - Istituto Nanoscienze - Centro S3 Via Campi 213/A, 41125 Modena, Italy
(4) University of Perugia, Strada di Pentima 4, 05100 Terni (TR) Italy
Introduction and aim
Nowadays, there is an increasing demand of new high
performance materials in terms of enhancement
mechanical and tribological properties in order to meet
the severe conditions required in some different
application areas as aerospace and defence, industrial
machinery, automotive, oil and gas, as well as medical
implant technology.
In this context, polymeric nanocomposites represent
new possibilities for innovative product development in
the future. Nanoparticle incorporation may lead to
composite materials with superior mechanical and
tribological properties like modulus, strength and
toughness, and especially wear resistance and friction
reduction [1-3]. In this context, their further
development and characterization are one of the main
goals of synergistic cooperation between the Sup&rman
laboratory of University of Modena e Reggio Emilia
(Italy) and the STM laboratory of University of Perugia
(Italy).
Among the different scientific activities of Sup&rman
laboratory, it is worth to note the ones related to the
understanding of tribology principles of polymeric
nanocomposities:
(i) development of innovative methodologies for testing
tribosystems under special environment, operating
conditions and geometric contact to mime several
industrial applications by means of tribological testing,
taking into account a wide range of loads, speeds,
lubricants and temperatures.
(ii) monitoring and controlling the wear phenomena that
is critical for an effective design strategy. In particular,
the wear mechanism is studied using both chemical and
physical analytical tools, such as infrared spectroscopy
based on Fourier transform (FT-IR), X-ray photoelectron
spectroscopy (XPS), scanning electron microscopy
(SEM), atomic force microscopy (AFM) and
profilometry (Fig. 1).
As far as STM activities in the field of nanocomposities
are concerned, they can be schematized as follows:
(i) development and production of engineered
nanopolymers aimed to improve the performance of
different matrices used in several application field, such
as automotive, aerospace, commodities and packaging.
(ii) analysis and optimization of the different parameters
which characterise the dispersion of nanoparticle into the
polymer during the injection moulding process in order
to increase some of the properties of the final composite.
(iii) study of mechanical, dynamic-mechanical and
rheological properties of materials, by means of tension
and compression test, ball-drop impact test, dynamic
mechanical thermal analysis (DMTA) and rotational
viscometers (RV).
Fig. 1: Wear track characterization by means of (a) FTIR
spectra, (b) SEM image, (c) AFM profile and (d) 3d
Profile
To effectively design polymer nanocomposites for
industrial applications, it is necessary to understand the
effects of nanoparticles on final proprieties of the
polymers. In this project, systematic studies are carried
out on the variability of the structural and mechanical
properties as function of the different used nanofiller.
Furthermore, the overall mission is to find a correlation
between the structural and mechanical changes with the
tribological proprieties of thermoplastic nanocomposite
due to the inclusion of nanoparticle. This will allow to
design nanocomposite materials by selecting ad hoc
nanofillers in order to increase their efficiency for
mechanical engineering and metal replacement
applications.
Experimental and discussion
In this study, a PEEK matrix has been used as ideal high-performance
materials for mechanical and tribological
applications to fabricate nanocomposite incorporating
nano-sized Al2O3, hexagonal-BN, SiO2 and Wollastonite
[4-6]. The samples are produced by a micro compounder

2. NANOTECHITALY2012
extruder coupled with micro an injection moulding
machine. The obtained injection moulded samples were
then chemically and physically characterized to study the
effects of material composition on the properties of the
final products.
Fig. 2: (a) Micro compounder extruder, (b) micro
injection moulding machine, (c) moulded polymeric disc
and (d) tensile test specimens.
In particular, their crystallinity degree has been studied
with differential scanning calorimetry (DSC), X-ray
diffraction (XRD) and FT-IR techniques following the
work of Chalmers in 1984 [7].
Furthermore, their mechanical properties have been
studied by means of tensile test in standard condition and
at high temperatures, 130 °C, just below the glass
transition. The friction and wear studies were carried
out by sliding a 100Cr6 steel ball with a diameter
of 4 mm against the nanopolymer discs using CETR
UMT-2 tribometer (Fig. 3). Two constant normal loads
(5 and 10 N), two temperature conditions (25° and 130°)
and a linear speed of 2 ms-1 were applied on the samples
during the tribological tests running for 1 hour. The wear
rate has been evaluated by using a stylus profilometer.
Fig.3 The schematic drawing of the ball-on-disc test.
The worn surfaces of the sample were investigated by
SEM to examine the potential tribological damage
mechanisms.
The results have provided useful and important
information about the influence of the studied nanofillers
on the level of cristallinity of PEEK nanocomposites and
their influence on mechanical and tribological properties.
The reached conclusions could have interesting
industrial implications in nanocomposite design.
References
[1] S. Komarneni, “Nanocomposites”, Journal of
Materials Chemistry, 2, 1219-1230, 1992.
[2] R. Roy, “Purposive design of nanocomposites: entire
class of new materials,” Materials Science Research, 21,
25-32 1986.
[3] K. Friedrich, and A.K. Schlarb, “Tribology of
Polymeric Nanocomposites” Elsevier 2008
[4] A. M. Díez-Pascual, M. Naffakh, C. Marco, G. Ellis,
M. A. Gómez-Fatou, "
High-performance
nanocomposites based on polyetherketones", Progress in
Materials Science 57, 1106–1190, 2012
[5] G. Zhang, A.K. Schlarb, S. Tria, and O. Elkedim,
“Tensile and tribological behaviors of PEEK/nano-SiO2
composites compounded using a ball milling technique”
Composites Science and Technology, 68, 3073-3080,
2008
[6] J. Tharajak, T. Palathai and N. Sombatsompop,
"Tribological Properties of Flame Sprayed Hexagonal
Boron Nitride/Polyetheretherketone Coatings" Advanced
Materials Research, 410, 333-336, 2012
[7] J. M. Chalmers, W. F. Gaskin and M. W. Mackenzie
“Crystallinity in poly(aryl-ether-ketone) plaques studied
by multiple internal reflection spectroscopy”, Polymer
Bulletin, 433-435, 1984
Biosketch
Alessio Passalacqua received the Master and Ph.D.
degrees in Chemistry from the University of Modena e
Reggio Emilia, Italy, in 2002 and 2007, respectively. He
has currently a research fellow of Interdipartimental
Center for services and applied research in high
mechanics and motoring InterMech-MO.RE, University
of Modena e Reggio Emilia. His current research
interests include the design and characterization of
polymer-based composites and nanocomposites with the
aim of improving their mechanical, tribological,
electrical-magnetic, and chemical-physical properties.
Contacts
Alessio Passalacqua, Department of Physics, University
di Modena e Reggio Emilia, Via Campi 213/A, 41125
Modena, Italy
Phone: (+39) 059 205 5729
Email: alessio.passalacqua@unimore.it