Sustainable use of plastics combines the right material choice, efficient production and recycling. The first step in recycling is correct sorting.
Resin identification codes
The number inside the triangle on a product shows the polymer type:
- 1 – PET: Bottles, food packaging
- 2 – HDPE: Drums, crates, caps
- 3 – PVC: Pipes, profiles, cables
- 4 – LDPE: Film and bags
- 5 – PP: Containers, caps, automotive parts
- 6 – PS: Foam and rigid packaging
- 7 – Other: PC, PA, ABS and blends
Why should they not be mixed?
Different polymers have incompatible melting temperatures and chemistry. For example, PVC contaminating PET or PE degrades during processing and seriously reduces product quality. That is why pure, clean streams are far more valuable in mechanical recycling.
What can be done in production
- Feeding production scrap and sprue or runner waste back into the process at suitable ratios, within the limits where material properties are preserved
- Designing products from a single polymer so they are easy to separate
- Reducing unnecessary wall thickness and extending product life
Keep in mind that each reprocessing cycle can slightly shorten the polymer chains, so the share of recycled material should be set according to the requirements of the application.