Production methods summary
The manufacture of poly(chloroethene) takes place in three stages:
- Manufacture of chlorine from sodium chloride
- Making the chloroethene monomer
- Polymerisation of chloroethene monomer to make the polymer
Chlorine is produced by the electrolysis of a solution of sodium chloride.
There are currently three different designs of electrolytic cell in
use, and all produce sodium hydroxide and hydrogen in addition to chlorine.
Click here to find out more about chlorine
The monomer is often referred to as "VCM", vinyl chloride
monomer. Vinyl chloride is the common name for chloroethene. Two methods
are available for its production:
- Most monomer is made from ethene via 1,2 dichloroethane, using two
parallel chlorination reactions. This is a well-established process,
but improvements are continually being made to increase productivity
and reduce environmental impact. For more
details follow this link.
- Chloroethene can also be made from ethane. Although the chemistry
of this is well understood, turning it into a viable industrial process
has been a challenge. The advantages are substantial both in terms
of productivity and the effect on the environment. Find
out more by clicking here.
Polymerisation is a completely separate process from monomer production.
Some PVC manufacturers do not make their own chloroethene monomer, but
buy it to use in the manufacture of PVC products. .Click
here for more details of the polymerisation process
Like many other plastics, PVC can be recycled once it reaches the end
of its useful life. This is particularly important as it tends to be used
in long-life products that would not easily decompose in landfill. More
information about the disposal issues surrounding PVC is given in the
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