Visit Specac at ARABLAB and analytica

Make sure to come by our tradeshows this March - we’ll be attending Analytica Munich and Arablab. You can view our award-winning Manual Press and view some of the new products we’ll be bringing with us.

Detection of Polymer Impurities in Recycled Plastics Using Chemometric Analysis of ATR Spectroscopy

Learn how the Specac Quest can be used to quickly identify impurities in your plastic materials.

As concern grows over the amount of waste we send to landfill, demand for the ability to recycle has increased particularly for plastic waste. Separating different types of polymers is essential to ensure the recycled product is suitable for reuse. Although every effort is made to ensure a pure recycled plastic is obtained, contamination is inevitable and therefore methods are required to quantify impurities. Here we have used FTIR spectroscopy coupled chemometric analysis to analyse polypropylene (PP) impurities in polyethylene (PE).

Chemometrics is the application of statistical tools to the measurement of chemical properties. One of these tools is Partial Least Squares (PLS) analysis, a method to find the fundamental relationship between two related matrices. In our case the first matrix is comprised of the ATR-FTIR spectra, whilst the second matrix is the sample composition data. A model is first constructed using spectra of known composition. The model is validated against further spectra of known composition and once validated can then be applied to swiftly determine the composition of unknown real-world samples.

The Specac QuestTM single reflection ATR is designed for use in the mid and far IR. The Quest features an all reflective gold coated optical design based on Specac’s proprietary Synopti-Focal array technology:

• Excellent spectral quality due to the Quests high throughput capability
• Choice of four easily interchangeable ATR crystal pucks: Diamond, ZnSe, Si and Ge
• Specular reflectance puck, flow through anvil and liquid puck options available and a heated puck option under development
• Monolthic Diamond design offers superior robustness and durability compared to other diamond wafer designs available on the market
• Suitable for Mid and Far IR (10000-40 cm) depending on choice of crystal
• Reproducible 40 lb load applied with a slip-click loading tower