The mechanical recycling, the most used way for plastic recycling is routinely applied by almost all the plastic manufacturers for processing scraps but is also used by specific processors for post-consumer recycling.
Plastic processing generally needs high temperatures, shears, pressures and other aggressive conditions when service life leads to long exposures to oxygen of air at more or less moderate temperatures, humidity, light irradiation, water and chemical expositions … Recycling itself involves physical and chemical damages during grinding and melting.
All these aggressions favour oxidation, chemical structure changes, pollution, desorption of additives, etc. as we can see on figure 1 displaying the main effects of processing and service life. However it is possible to improve the recyclate properties by intelligently using additives to find again original properties or even sometimes better ones.
From economical and environmental points of view, mechanical recycling is a very exciting solution as claimed by several