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Abstract  

DMA and solid state 13C NMR techniques were used to measure historical parchment samples within the framework of the project (MAP) Micro Analysis of Parchment (EC contract No. SMT4-96-2101) in collaboration with the School of Conservation in Copenhagen. DMA was used in both thermal scan and creep modes. Thermal scans provided information on the transitions associated with the collagen polymer. Microthermal analysis was also used to obtain information on the topography and thermal conductivity of sample areas of 100 μm. Localised heating enabled measurements of softening transitions in the sample. This behaviour is influenced by the chemical composition of parchment. 13C NMR provided information on the carbon atoms associated with the polypeptide chains of the collagen in parchment. The behaviour of samples immersed in water and measured in DMA creep mode was used to measure the shrinkage behaviour of the parchment samples. The different but complementary techniques provided a means for characterising the physicochemical state of parchment samples.

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Journal of Thermal Analysis and Calorimetry
Authors: G. Della Gatta, E. Badea, R. Ceccarelli, T. Usacheva, A. Maši?, and S. Coluccia

Summary  

Environmental impact on parchment was investigated by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Parchments subjected to accelerated ageing and old parchments were compared to evaluate quality and extent of deterioration. Stability of fibrillar collagen within parchment was determined from the changes in thermodynamic parameters associated with thermal denaturation. Parchment surface was characterised, and specific morphological criteria were selected for damage assessment. The thermodynamic and morphological changes of collagen induced by deterioration are discussed, and their correlations are proposed as a means of ranking damage in old parchments.</o:p>

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Abstract  

To reveal the fire injuring of parchment, the changes in the thermal behaviour of some goat parchments, obtained from skins originating from different animals, as a result of thermal aging were determined by thermal analysis methods (DSC; simultaneous TG/DTG, DSC; micro hot table (MHT)). Thermal aging of parchments was revealed to bring about the decrease in shrinkage temperature, absolute value of enthalpy of denaturation in water and some changes in non-isothermal parameters characteristic for dehydration process in static air atmosphere. The results obtained by DSC analysis performed in N2 and O2 flows as well as those obtained by simultaneous TG/DTG, DSC analyses have shown that both softening (melting) process parameters and parameters of thermo-oxidative processes have not been changed by thermal ageing. The results obtained by thermal analysis methods were correlated with those obtained by microscopic investigation of parchment samples immersed in water and scanning electron microscopy (SEM). The application of these microscopic techniques has revealed the morphology changes in the investigated parchments as a result of thermal degradation.

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Abstract  

The hyphenated thermal analysis-mass spectrometry technique (TA-MS) was applied for the investigation of the thermal behavior of reference and aged parchment samples. The kinetic parameters of the process were calculated independently from all recorded TA and MS signals. The kinetic analysis showed the distinct dependence of the activation energy on the reaction progress. Such behavior is characteristic for the multistage mechanism of the reaction. The comparison of the kinetic parameters calculated from the different signals i.e. TG, DSC, MS for H2O, NO and CO2, however, indicated that they were differently dependent on the aging of the sample. For the parchment samples, the aging almost does not change the kinetics of the decomposition calculated from the DSC data: the influence of aging seems to be too negligible to be detected by these techniques. On the other hand, the much more sensitive mass spectrometric technique applied to the kinetic analysis allowed monitoring of visible changes in the thermal behavior of the parchment samples due to the aging process. The influence of aging was especially visible when the MS signals of water and nitric oxide were applied for the determination of the kinetic parameters. The applied method of the kinetic analysis allowed also the prediction of the thermal behaviour of reference and aged parchment samples under isothermal and modulated temperature conditions. Presented results have confirmed the usefulness of thermoanalytical methods for investigating behaviour of such complicated systems as leather or parchment.

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Introduction Parchment conservation practice has long time been regarded and executed as a craft governed by secrecies and empiricism, while parchment conservation science has started to develop only in the second half of

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Abstract  

The TG, DTG, DTA methods were used for investigation of the thermal degradation in static air atmosphere of some collagen-based materials (some sorts of collagen, recent manufactured parchments and tanned leathers, patrimonial (historical) leathers). At the progressive heating, all investigated materials exhibit two main successive processes, associated with the dehydration and thermo-oxidative degradation. The patrimonial leathers were divided in two groups, namely: a group containing the majority of the analyzed materials, for which the rates of the thermo-oxidation process are substantially lower than those corresponding to the recent manufactured leathers, and a group for which the rates of thermo-oxidation process are closed to those corresponding to the recent manufactured leathers. Consequently, if by the thermal analysis in air atmosphere of a leather sample, a value of the rate of the thermo-oxidation process smaller than that corresponding to the recent manufactured leathers is obtained, then the analyzed leather is a patrimonial one. The reciprocal statement of this qualitative criterion for distinction between recent manufactured leather and patrimonial leather is not valid. The DSC analyses of collagen-based materials were performed in air (DSC(air)) and in water (DSC(water)). The denaturation process takes place at lower temperatures in water than in air. Unlike recent manufactured leathers and parchments, each patrimonial leather exhibits on DSC(water) plot 2-4 peaks. Consequently, the number of peaks from DSC(water) curve could be another qualitative criterion for distinction between a recently manufactured leather and a patrimonial leather.

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Abstract  

A comprehensive investigation has been made of a set of 14th to 16th-century parchment bookbindings from the Historical Archives of the City of Turin. Advanced physico-chemical techniques, such as thermal analysis (DSC, TG and DTA), spectroscopy (FTIR and UV-Vis-NIR), scanning electron microscopy (SEM) and unilateral nuclear magnetic resonance (NMR-ProFiler) were employed to assess specific deterioration processes occurring at different levels in the hierarchical structure of parchment. Changes in the measured physical and chemical parameter values of parchment due to interaction with the environment were used to identify possible deterioration pathways.

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Abstract  

The thermo-oxidative degradation of a parchment recent manufactured from a goat skin has been investigated by TG/DTG, DSC simultaneous analysis performed in static air atmosphere, at six heating rates in the range 3–15 K min−1. At the progressive heating in air atmosphere, the investigated material exhibits three main successive processes occurring with formation of volatile products, namely the dehydration followed by two thermo-oxidative processes. The processing of the non-isothermal data corresponding to the first process of thermo-oxidation was performed by using Netzsch Thermokinetics—a Software Module for Kinetic Analysis. The dependence of activation energy, evaluated by isoconversional methods suggested by Friedman, and Ozawa, Flynn and Wall, on the conversion degree and the relative high standard deviations of this quantity show that the investigated process is a complex one. The mechanism and the corresponding kinetic parameters were determined by Multivariate Non-linear Regression program. Three mechanisms, one consisting in four successive steps and two others in five successive steps, exhibit the best F-test Fit Quality for TG curves. It was also used the previously suggested criterion, according to which the most probable process mechanism correspond to the best agreement between E FR = E FR (α) (E FR is the activation energy evaluated by isoconversional method suggested by Friedman; α is the conversion degree) obtained from non-isothermal experimental data and activation energy values, E iso, obtained by applying the differential method to isothermal data simulated using non-isothermal kinetic parameters. According to this last criterion, the most probable mechanism of parchment oxidation consists in four successive steps. The contribution of the thermo-oxidation process in the parchment damage by natural aging is discussed.

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Up to now, the Propertius has been identified with a parchment codex with a marginal commentary in the hand of Gioviano Pontano that is now Valencia, Biblioteca de la Universitat MS. 725 (791): thus Mazzatinti (n. 12) 15; Omont (n. 21) 466; De

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The damage in the patrimonial books from Romanian libraries

Thermal analysis methods and scanning electron microscopy

Journal of Thermal Analysis and Calorimetry
Authors: P. Budrugeac, L. Miu, and M. Souckova

Abstract  

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�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.

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