Polymerisation of Ethene - Chemistry.

Ethene put under pressure and heated
with a catalyst
will polymerise
(make long chains of atoms)
to form poly(ethene).
Note that there are no double bonds in the polymer.
Poly(ethene) is an alkane. It is a saturated hydrocarbon.
Depending on the reaction
conditions and the type of catalyst used,
ethene can make either HDPE
or LDPE.
HDPE is High
Density Poly(Ethene)
and has a higher crystallinity
and a higher melting
point than LDPE
(Low Density Poly(Ethene).
HDPE is stronger
and stiffer
than LDPE.
A polymer which is formed from monomers added
together
where no other
substance is produced is called an
addition
polymer.
Examples of addition polymers
are
poly(ethene), poly(propene),
poly(tetrafluoroethene) - PTFE,
poly(chloroethene) - PVC and
poly(phenylethene) - polystyrene.
Chloroethene used to be called vinyl chloride.
The polymer is still called
polyvinyl chloride, or PVC.
Phenylethene used to be called styrene.
The polymer is still called
polystyrene.
A polymer is often written in the form

The brackets contain the repeat unit.
The small n means that there are many of them.
Below are some examples of the
repeat units of polymers.

See properties and uses of polymers.
Headings Polymers Search Questions ![]()
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