Once re-processed back into a usable feedstock, PVC recyclate needs to be transformed into new products using similar techniques to those used when working with virgin PVC (such as extrusion, moulding and calendaring).
Mechanically recycled material will inevitably contain a combination of processing and performance additives (such as stabilizers, pigments, plasticisers, etc.) that were present in the original PVC products.
If the recyclate has been re-processed from a single type of product (as is typical in post-industrial waste), this may already be a PVC compound that is usable without the addition of any further additives. When the recyclate has come from mixed sources (or the manufacturer wishes to re-colour it or use it in a special type of process for which a particular property is needed) it may be blended with new additives to achieve the required performance characteristics.
Some products – like road traffic cones - have been produced using recycled PVC for many years. But the range of recycled products is rapidly increasing. As it is uneconomic to produce recycled material of a particular colour or cosmetic appearance, it is common for product manufacturers to incorporate recycled material within the interior of a product, where it is unseen, and use virgin material in the outer layers where a specific appearance or finishing needs to be maintained.
Unlike many types of plastics which can only be recycled a very limited number of times, PVC can maintain its physical strength through repeated recycles. Therefore it is quite possible that in the future, when society has learned to be more resource efficient and most products will contain recycled content, PVC could be re-processed through multiple product lives. With products like windows and pipes, which are used for more than 60 years, PVC could sit alongside diamonds as a material that practically ‘lasts forever’ and never needs to be thrown away.