Meaning
Material proportions defined in plastic waste accounting quantify the percentage of polymer originating from consumer products that have completed their intended end-use lifecycle. Packaging manufacturers and injection moulders measure post-consumer recycled content to comply with statutory recycling targets and corporate sustainability mandates. The metric applies to reprocessed polyolefin and PET resins recovered from municipal recycling streams.
It excludes pre-consumer industrial scrap, internal factory regrind, and off-spec resin generated during primary manufacturing.
Material Sourcing
Municipal waste collection, automated optical sorting, and wash plant operations convert discarded household packaging into cleaned plastic flake. Re-compounding this flake produces pellets containing certified post-consumer recycled content for direct use in container and automotive part production. Incomplete removal of food residues and secondary polymers introduces odor and particulate contamination into the recycled resin melt.
Moulding Performance
Incorporating recycled feedstock into virgin resin alters melt flow behavior and mechanical impact performance. Moulders processing high percentages of post-consumer recycled content experience melt pressure fluctuations that cause part weight variation and short shots in multi-cavity tools. Adjusting injection speed profiles and cavity packing pressures compensates for lot-to-lot viscosity shifts inherent in recycled feedstock.
Quality Variation
Contaminant inclusions and broad molecular weight distributions lower stress crack resistance and tensile elongation in finished parts. Material testing must confirm property consistency before approving recycled resin lots for structural moulding applications.
