Technical Guide – What is PVC–U/UPVC?

In 1912, Fritz Klatte discovered the basic principles for the industrial production of PVC-U/vinyl, a process which can be summarised in five steps:

(1) Electrolysis(2) of salt(1) produces chlorine(3).
(2) Ethylene (6) is obtained after refining(5) the oil(4) and cracking naphtha.
(3) Chemical synthesis(7) of these two elements produces the 'monomer', vinylchloride(8), in gaseous form.
(4)Polymerisation(9) of this monomer structure produces the polymer, poly-vinylchloride, or PVC-U; an inert powder.
(5) The PVC-U resin(10) is mixed (compounded) with various additives(11) in order to form variations with different properties. The result is a fairly fine powder or granules(12).