Industrial Compostability Passed off as Home Compostable on Shelf
Finished packaging claims demand independent home compostability certification because industrial resin testing excludes ambient degradation and converting inks.
FTIR Spectrometry
Chemical Fingerprinting
Analytical laboratory techniques utilizing infrared light identify the chemical structure of organic compounds by measuring their absorption of different wavelengths. Applying FTIR spectrometry to packaging substrates allows technicians to quickly identify the polymers, coatings, and adhesives used on paperboard or plastic films. This analysis works by exposing the sample to infrared radiation and recording the unique absorption pattern, which resembles a chemical fingerprint.
It provides a non-destructive method for confirming whether a barrier layer contains synthetic or bio-based polymers.
Analysis Protocol
Spectrum libraries are used to match the collected absorption curves against known reference materials. During FTIR spectrometry, the resulting spectrum is compared to databases of common packaging plastics like polyethylene, polylactic acid, or wax coatings. This allows quality control labs to verify the purity of incoming shipments and detect any unauthorized polymer substitutions.
The test requires very little sample preparation, making it an efficient tool for high-throughput testing in converting plants.
Quality Control
Converting operations rely on this technique to debug adhesion and heat-sealing issues on the production line. When a roll of laminated film fails to seal properly, a quick run on the spectrometer can reveal if the wrong coating was applied. This saves hours of downtime during a high-speed packaging run.