NMR investigation of degradation processes of ancient and modern paper at different hydration levels

The degradation process of cellulose-made materials was investigated bymeans of nuclear magnetic resonance (NMR) spectroscopy, with particularemphasis on the role of water and on the hydration mechanism of cellulose fibrils.To accomplish this, the structure and dynamics of water within ancientand modern samples with different aging histories were investigated. The resultsmainly indicated that hydrolytic and oxidative reactions provoked theformation of acidic by-products. Furthermore, degradation processes wereenhanced by higher amounts of water because of the progressive consumptionof the amorphous regions of the cellulose. We propose NMR experimentsas a benchmark for characterization of the degradation state of paper, as wellas for investigating the effectiveness of restoration treatments.