Quantitative diffuse reflectance infrared spectroscopy of cotton fabrics treated with a cyclodextrin derivative finishing auxiliary

For the textile industry, infrared spectroscopic methods that are based on diffuse reflectance measurements can be used for the non-destructive analysis of polymer composition of the fabric materials including their auxiliaries. Our diffuse reflectance accessory allows the contact-free measurement of sample spots located on large and bulky samples with a sufficient spectral signal-to-noise ratio. In this study, the results of a quantitative analysis of a reactive auxiliary (cyclodextrin derivative) applied on cotton fabrics up to 5% (by weight) are shown and limitations of the diffuse reflectance measurement technique discussed. Reference values had been provided by the laborious Kjeldahl method. Multivariate calibration based on partial least squares was employed using the specific bands of the cyclodextrin derivative within the spectral interval of 1900–1480 cm−1, providing prediction results with around 5% of relative standard prediction error, based on mean sample population concentrations