advanced-materials-nano-engineering-2018-posters

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Page 70
Volume 4
December 10-12, 2018
Rome, Italy
Nano Research & Applications
ISSN: 2471-9838
Advanced Materials 2018
Nano Engineering 2018
JOINT EVENT
22nd International Conference on
Advanced Materials
and Simulation
&
22 nd Edition of International Conference on
Nano Engineering &
Technology
Our mainmotivation is to analyze the deformationmechanisms
of polymers inconfinement fromexperimentalmeasurements
that ensure an in situ observation of the phenomena from
yielding (scratches) to viscoelastic properties. In this vein, the
behavior of the sheared interfacial layer when a spherical tip is
sliding on a polymer surface still raises many questions. The
main objective of this study is to initially model this unknown
interfacial layer by phospholipid multilayers in a boundary
lubrication case. Tribological experiments on these ultrathin films
were performed to identify the influence of parameters such
as temperature, relative humidity, sliding speed of the tip and
applied mean contact pressure. For instance, an analysis based
on Eyring model concludes that with an increase of humidity rate
the value of the activation energy Q decreases. In parallel the
clear influence of moisture on the thickness of water film in the
structure of phospholipid layers was demonstrated with neutron
reflectivity experiment. In particular, for three layers the thickness
of water film between the supported bilayer and third floating
monolayer can be ranged from 0.3 nm to 1.2 nm by increasing
the moisture content from 30% to 90% (Figure). From these
results the underlying question is how to determine the velocity
profile and locate the slip plane in such a friction experiment.
We propose to associate velocimetry and tribology experiments
(Tribo-FRAPP) to have more information on microscopic level
and on localization of sliding plane in the friction experiment. For
instance, preliminary studies on DSPC three layers have shown
that at low speed all three layers are moving and the slip plane
whereas at higher speed only the third layer moves. In this case,
the slip plane is located within the water film.
Anne Rubin
Charles Sadron Institute-Strasbourg University, France
Nano Res Appl 2018, Volume 4
DOI: 10.21767/2471-9838-C7-028
Tribology and velocimetry experimental
coupling: an original setup to study confined
and sheared phospholipid layers