QUALITATIVE IDENTIFICATION OF POLYMERIC MATERIALS USING NEAR-INFRARED SPECTROSCOPY

During the past decade near-infrared (near-IR) spectroscopy has become a widely used analytical technique. Most applications have been for quantitative analysis. In the past several years, near-IR spectroscopy has been successfully used for qualitative analysis through the use of computer-assisted data processing. Two major methods of data analysis have yielded successful results: discriminant analysis and spectral searching. Discriminant analysis is useful for discrete wavelength spectra obtained with bandpass filters and continuous spectra obtained with a scanning monochromator. Spectral searching of first derivative spectra is used for continuous spectra from a scanning monochromator. In this study, we demonstrate the ability to qualitatively identify various textile fibers and thermoplastic polymers with near-IR spectroscopy using these two methods.