Brochure: Carbon Additives for Polymer Compounds - Timcal Graphite
Brochure: Carbon Additives for Polymer Compounds - Timcal Graphite
Brochure: Carbon Additives for Polymer Compounds - Timcal Graphite
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Introduction to TIMREX®<br />
<strong>Graphite</strong> and Coke<br />
<strong>Graphite</strong> finds wide application thanks to its<br />
favourable combination of properties such as:<br />
• low friction, chemical inertness and<br />
absence of inherent abrasiveness;<br />
• high thermal conductivity, thermal<br />
stability and electrical conductivity;<br />
• film <strong>for</strong>ming ability on metal surfaces;<br />
• relatively inoffensive nature of both<br />
powders and products of combustion.<br />
These properties are a consequence of the lamellar<br />
graphite structure and the anisotropic<br />
nature of chemical bonding between carbon<br />
atoms. In graphite, three sp 2 hybrid orbitals<br />
(each containing one electron) are <strong>for</strong>med<br />
from the 2s and two of the 2p orbitals of each<br />
SEM picture of TIMREX® <strong>Graphite</strong> showing the perfect<br />
crystalline structure.<br />
Lc<br />
c/2 = Interlayer distance<br />
Lc = Crystallite height<br />
carbon atom and participate in covalent bonding<br />
with three surrounding carbon atoms in the<br />
graphite planes. The fourth electron is located<br />
in the remaining 2p orbital, which projects<br />
above and below the graphite plane, to <strong>for</strong>m<br />
part of a polyaromatic π-system.<br />
Delocalisation of electrons in π-electron system<br />
is the reason of graphite’s high stability<br />
and electrical conductivity. Interlamellar bonding<br />
was once thought to be weak and mainly<br />
the result of Van der Waals <strong>for</strong>ces, however, it<br />
now appears that interlamellar bonding is rein<strong>for</strong>ced<br />
by π-electron interactions. <strong>Graphite</strong> is<br />
there<strong>for</strong>e not intrinsically a solid lubricant and<br />
requires the presence of adsorbed vapours to<br />
maintain low friction and wear.<br />
c/2<br />
c<br />
HoW TIMREX® GRApHITE And CokE<br />
poWdERS ARE pRoduCEd<br />
TIMREX® pRIMARY SYnTHETIC GRApHITE<br />
TIMREX® Primary Synthetic <strong>Graphite</strong> is produced<br />
in a unique highly controlled graphitization<br />
process which assures narrow specifications<br />
and unequalled consistent quality thanks to:<br />
monitoring of all production and processing<br />
stages, strict final inspection, and clearly defined<br />
development processes.<br />
TIMREX® Primary Synthetic <strong>Graphite</strong> shows<br />
unique properties thanks to the combination of<br />
a consistent purity, perfect crystalline structure<br />
and well defined texture.<br />
TIMREX® nATuRAL FLAkE GRApHITE<br />
TIMREX® Natural Flake <strong>Graphite</strong> is produced<br />
in a wide range of products distinguished by<br />
particle size distribution, chemistry and carbon<br />
content. <strong>Timcal</strong> mines the graphite from its own<br />
source in Lac-des-Îles, Quebec, Canada. Further<br />
processing can be done either in Lac-des-Îles or<br />
in our processing plant in Terrebonne, Quebec,<br />
Canada. All TIMREX® “Naturals” are thoroughly<br />
controlled in our laboratories to ensure quality,<br />
consistency and total customer satisfaction.<br />
TIMREX® CokE<br />
TIMREX® Petroleum Coke is calcined at appropriate<br />
temperature with low ash and sulphur<br />
content, well defined texture and consistent<br />
particle size distribution.<br />
5<br />
the product