Characterization of Degradation of Cotton Cellulosic Fibers Through Near Infrared Spectroscopy

AbstractNear infrared (NIR) spectroscopy has been found to be one of the most important characterization tools for polymeric materials based on comparatively simple NIR-favorable chemical groups (i.e., C–H, O–H, and N–H). This paper focuses on characterizing degradation of cotton cellulosic fibers in a historical textile—‘Curtain Dress’ in the famous movie Gone With the Wind through NIR spectroscopy, and investigating morphological and molecular changes associated with appearance change such as discolorations in the same cotton textiles. In this study, we did on-site testing on the ‘Curtain Dress’ with the Brimrose Luminar 5030 NIR-analyzer and analyzed the NIR spectroscopy results at eight locations where different degrees of discoloration occurred on the dress. The study identified the wavelength bands according to NIR spectral absorbancies of the typical functional groups in cellulosic fibers such as C–H, C–O and O–H stretches, compared the absorbance intensities at three main wavelengths, and investigated discoloration in different areas via principal component analysis. The combination factor scores of the 1st and 2nd principal components, which accounted for 99.09 % variance of vibrations within various groups in a molecule measured through NIR, reflected effectively morphological changes in the fiber’s molecular structure and degrees of discolorations.