Near infrared assessment of biodegradability and mechanical properties of paper made of cellulose sulfate bleached coniferous pulp with addition of cationic starch and resinous adhesive

Abstract

The goal of this work was to develop Fourier-transform-near-infrared-spectroscopy-based methodology for monitoring kinetics and estimating the biodegradation rate of coniferous pulp paper. Two experiments with paper-degrading fungi were tested: one with Chaetomium globosum alone and the other with a mixture of Aspergillus niger, Trichoderma viride, and Penicillium funiculosum. Paper sheets made of fibers with the addition of 0, 2, 3, or 5% of cationic starch and resinous adhesive were used as test samples. In order to quantify the resistance of the paper to biodegradation, tests of breaking length and evaluation of the degree of fungal infestation were performed during infestation. It was found that addition of cationic starch and resin adhesives improved mechanical properties of paper; however, it also increased susceptibility to fungal colonization. Degradation of paper colonized by C. globosum was more advanced and exhibited more rapid kinetics. Spectral analysis revealed that spectra were most varying in bands 4283, 4400, 4742, and 4808 cm−1, which correspond to –CH, and –OH functional groups of cellulose and hemicelluloses. Differences in spectra were in good agreement with the reference methods; therefore this technique has potential for monitoring the paper biodegradation process and predicting changes in the paper's mechanical properties.