How NIR Identifies Different Polymer Types
Different polymers contain molecular structures that produce characteristic near-infrared absorption patterns. NIR analysers measure these patterns and compare them with reference spectra or classification models to determine the likely polymer type.
In recycling operations, NIR can support identification and separation of plastic materials that may appear visually similar. Depending on the equipment, measurements can be performed using handheld instruments or integrated into automated sorting systems.
Performance depends on the plastic type and condition. Dark or carbon-black-filled plastics can absorb near-infrared light strongly, making identification difficult for conventional NIR systems. Contamination, coatings, multilayer packaging, surface condition, and additives may also influence results. Reliable sorting requires suitable reference data and validation for the materials being processed.
Reviewing NIR for Polymer Identification
For more detail on the measurement method, review PAS’s overview of Near Infrared Spectroscopy technology. To assess suitable instruments, explore the available NIR analysers through Portable Analytical Solutions, or get in touch to discuss polymer identification and material sorting requirements.