A comparative study investigating differing forms of hyperspectral imaging for the polymer identification and isolation of polymers

Hyperspectral imaging (HSI) is a type of spectroscopic technique enabling the user to obtain images with both spatial and spectral information. The experiments carried out in this paper investigated two HSI systems, a visible light and a near infrared (nIR) system to determine which would best be able to distinguish between samples of interest, in this case synthesised polymers and their starting materials. Principal component analysis (PCA) was used in order to resolve the contribution to the data from different samples. PCA separated out the spectral signals, clearly allowing different polymer signals to be distinguished. The separation was much greater with data collected using the nIR rather than visible light ranges. This study has shown that there are significant differences in the effectiveness of HSI in distinguishing between samples of interest, depending on the HSI wavelength range used.