Meaning
Post-consumer plastic packaging materials made from polyethylene or polypropylene undergo decontamination and re-pelletization for reuse in food contact applications. Producing recycled polyolefin food packaging requires strict decontamination efficiency to meet food safety authority regulations regarding chemical migration. The material class governs raw material sourcing criteria and final part migration limits.
It stops applying when the resin is diverted into non-food industrial applications or structural construction products.
Decontamination Efficiency
Deep cleaning processes use vacuum extraction and hot gas stripping to extract absorbed contaminants from recycled flake. Using recycled polyolefin food packaging mandates challenge testing with volatile surrogate chemicals to demonstrate effective cleaning efficiency. Residual chemical levels must satisfy safety thresholds before resin blending occurs.
Clean flakes yield safe virgin-blend ratios.
Regulatory Compliance
European and United States safety agencies require positive opinion evaluations and non-objection letters prior to commercial food contact use. Materials designated for recycled polyolefin food packaging must demonstrate that non-intentionally added substances remain below toxicological threshold limits. Challenge tests prove that decontamination processes remove model contaminants below five parts per billion.
Chemical testing verifies batch consistency before resin compounding. Sourcing traceability tracks post-consumer input streams from collection to finished packaging.
Property Degradation
Degradation during multiple processing lifecycles reduces melt flow uniformity and environmental stress crack resistance compared to virgin resins. Compensating for property loss in recycled polyolefin food packaging involves adding melt-strength enhancers and virgin resin diluents during extrusion compounding. Rheological drift alters mold filling behavior and part wall thickness uniformity.
Molders adjust injection pressure profiles to compensate for batch-to-batch viscosity fluctuations. Melt filtration removes insoluble particles that cause film pinholes or cosmetic flaws.
