6533b85efe1ef96bd12c05f0

RESEARCH PRODUCT

Reprocessing of Poly(Vinyl Chloride), Polycarbonate and Polyethyleneterephthalate

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Poly ethyleneterephthalate — PET- and Poly(vinyl chloride) — PVC — are two of the most frequently encountered polymers in post-consumer plastics. In particular, these polymers can be used for manufacturing the same products (bottles, for example) and therefore are often found in the same stream, even when the collection is done with separation. The recycling of PET and PVC is usually carried out by separating them and reprocessing the two homogeneous polymers. Indeed, the heterogeneous recycling of two polymers is at present almost impossible because of many problems: as their melting points are very different, at the processing temperature of PET severe degradation phenomena of PVC take place; the degradation of PET, in turn, is drastically accelerated by hydrochloric acid, that is the main product of the degradation of PVC; PVC is not sensitive to the presence of water, while PET can be easily degraded by hydrolytic chain scission and must be carefully dried before processing; the two polymers are strongly incompatible and, even if all the previous problems were overcome, the recycled material would have very poor properties [1].