The damage in the patrimonial books from Romanian libraries - Thermal analysis methods and scanning electron microscopy

The thermal analysis methods (TG, DTG, DSC, methods for shrinkage temperature evaluation) and scanning electron microscopy (SEM) were used for investigation of the thermal behaviour and surface morphology of some recent manufactured parchments and vegetable tanned leathers, patrimonial parchments and leathers proceeded from Romanian libraries. At the progressive heating in static air atmosphere and in the temperature range of 20-600 degrees C, all investigated materials exhibit three main successive processes, associated with the dehydration and thermo-oxidative degradations. The rate of the first thermooxidative process, temperatures corresponding to the maximum rate of the second thermooxidative process and shrinkage temperature were associated with the damage of the investigated materials due to environmental impact. Parchments and leathers surfaces were characterized by SEM, and specific morphological criteria were suggested for damage assessments. These criteria were correlated with the results obtained by thermal analysis methods.