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The current research presents a new strategy for the treatment of degraded historical leather. Digital microscope, pH, FTIR and SEM analyses were used to evaluate the degradation of two leather bookbindings dated back to the fourteenth century. A conservation process was executed and included cleaning and the filling of holes according to a new recipe in the field of leather conservation containing leather powder, anhydrous cellulose, cellulose powder, acacia arabica, gelatin powder and clay nanoparticles. The new recipe was evaluated on modern leather samples before and after their accelerated ageing by monitoring any changes in their pH and colour, along with differential thermal analysis before the filler was applied to the historic leather. Results showed that the acidity of the leather remained in its natural state and the leather did not exhibit any oxidation nor hydrolysis. Moreover, the evaluation process for the new recipe suggested that it could be a promising material for the filling of losses to leather especially as it is thermally stable and shows consistency with the acidity of leather. Furthermore, the new fill material is easy to manipulate and shows no significant shrinkage or change to its colour. [ABSTRACT FROM AUTHOR]

The present experimental study determined the thermal degradation stages for vegetable and chrome-tanned leathers (goat and sheep) at 90, 100, and 130 °C by using Fourier transform infrared spectroscopy (FTIR) and differential thermal analysis. Infrared spectra revealed that a temperature of 90 °C affected the adsorbed water band at 3400 cm−1. Moreover, this temperature slightly reduced the vibrations of amide II and amid III (1340 cm−1) confirming the preliminary decomposition of protein folds, but it is worth noting that the aliphatic side chains remained stable at this stage of aging. At 100 °C, there was a sharp rupturing in the phenolic-OH bond and side-by-side N–H vibrations decreased dramatically. The peak decomposition occurred at 130 °C, where the amide I and amide III intensities significantly increased, which can be considered indicative of protein unfolding. Those changes are substantiation of protein denaturation. Thermal analysis demonstrated that thermal aging significantly reduced the required temperature for the process of oxidation. The oxidation occurred at 217 °C in goat sample aged at 90 °C. Nevertheless, the reference sample suffered from oxidation at about 220 °C, while with increasing aging temperatures (at 100 and 130 °C), endothermic reactions were observed. Such reactions are usually associated with protein denaturation. [ABSTRACT FROM AUTHOR]

The main goal of this study was to study and evaluate the effect of linseed oil and glycerine emulsion a surface treatment on appearance and chemical composition of archaeological leather samples, which were taken from a historical leather book binding back to 1858, 1653 & 1472 A.D, have been treated with linseed emulsion then a visual assessment, pH measurements, thermal analysis methods (TGA), infrared spectroscopy (FTIR) study and mechanical properties determination were undertaken, to see if any significant structural or chemical differences could be detected between “untreated” and “treated” leather. No dramatic changes in functional groups on the leather surface, as monitored by infrared spectroscopy, occurred in the samples before and after treatment; pH values, however, show that emulation may give good results in decreasing the acidity of the treated leather. The emulsion enhanced thermal & mechanical properties of treated samples. [ABSTRACT FROM AUTHOR]