ENSACO® Conductive Carbon Black for polymer ... - Timcal Graphite

Influence of TIMREX ® Graphite
and Coke fillers in filled-PTFE
Wear resistance:
virgin PTFE shows much high wear as a result
of the destruction of the banded structure due
to easy slippage between the crystalline lamellae
in the bands.
The presence of well distributed carbon particles
in the filled PTFE partially avoid the slippage
between the crystalline lamellae in the
bands and therefore the wear resistance is
improved.
Deformation strength:
virgin PTFE deformation behaviour is somehow
similar to the mechanism previously
described. In someway the deformation phenomena
could be explained by the tendency
of slippage that occurs between the crystalline
lamellae. However, in this case the presence of
well distributed carbon particles in the filled
PTFE offers only a partial explanation to the
phenomena because also hardness of these
particles is important in determine an
improvement of the deformation behaviour.
Friction Coefficient:
the coefficient of friction for various filled
PTFE composites is weakly dependent upon
the incorporated filler, because a thin PTFE
film generally exists at the interface between
the body and counter-body. Consequently the
coefficient of friction is both similar in the
filled PTFE and virgin PTFE. This evidence is
true as long as no oversize particles are present
in the filler. In fact the presence of oversize
particles could lead to a radically modification
of the coefficient of friction. Because of that in
carbons as well as in other fillers is very important
the control of oversize particles.
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