Plastic/Polymer Identification
Spectroscopy is well-suited for measuring polymer identities. It provides rapid, accurate, and non-destructive material analysis for industrial and research applications.
The SR-3500 is a portable, full range UV/VIS/NIR spectrometer that can be used to:
- Accurately identify plastics for recycling to avoid contamination and potential processing problems
- Correctly sort polymer resins
- Sort and identify raw materials
- Measure raw material purity
- Analyze moisture content
The SR-3500 delivers a number of benefits for plastics identification:
- Rapid, reliable, and non-invasive measurement
- Cost-effective analysis
- Portability – take the analyzer to the application
- No sample prep necessary
- Easy to use DARWin SP Data Acquisition software
- Easy to use with 3rd party chemometric software for more in-depth analysis
NIR spectra can be attributed to the five major groups of plastic resins:
- Polyethylene terephthalate (PET)
- High density polyethylene (HDPE)
- Polyvinyl chloride (PVC)
- Polypropylene(PP)
- Polystyrene (PS)
NIR spectroscopy can be performed on starting materials, materials in process, and finished product, off-line in the lab, on- line separated from the processing stream, or in-line within the process itself.
Plastic identification applications can include:
- Accurately identifying specific plastics in recycling
- Measuring quality in thermoplastic production
- Incoming raw materials quality control
- Analysis of physical attributes including density and viscosity
- Final quality assessment of finished product
- Quantifying the constituent parts of polymers, including residual solvents and monomers
- Measuring and identifying additives
- Measuring water content
- Determining physical and chemical properties

No sample prep required, highly reliable with no moving parts, easy-to-use – the SR-3500 is a good match for plastic/polymer analysis and identification.

Transreflectance of three different plastic films measured with the SM-3500. Each scan took less than one second. DARWin SP Data Acquisition software allows for the combination of multiple scans in a single plot for comparison. Scans represent polyester (red trace), polystyrene (blue), and acetate (green) films.