FTIR-ATR spectroscopic analysis of changes in fiber properties during insulating fiberboard manufacture of beech wood

Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy was applied to trace changes in chemical fiber properties during the production process of insulating fiber mats. In combination with cluster analysis, FTIR spectra were used to interpret the homogeneity of the products. Beech wood (Fagus sylvatica L.) was used as a novel sustainable material for fiberboard production. The insulating fiberboards were either processed without binder or with potato pulp or potato starch as renewable binders and dried in a dryer or a microwave. FTIR spectral analyses revealed chemical modifications at the O-H association band of carbohydrates that distinguished the two different drying methods. Additions of plant-based renewable binders diminished the absorbance of the resulting products at characteristic wavenumbers in the IR. These decreases were closely correlated with the amount of added binder and thus have the potential to quantify binder additions to the fiberboards. Cluster analysis grouped FTIR spectra of samples from different production steps or processes correctly and therefore is an effective and simple technique for quality control of insulating fiberboards from renewable resources.