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This paper presents the limitations and potential of ATR-FTIR spectroscopy applied to the study of cellulosic textile collections The technique helps to differentiate natural fibres according to the content of lignin, pectin, hemicellulose, and wax, although some problematic issues should be considered. The spectral differences derived from the environmental humidity uptake and the plant composition are reviewed and discussed in the light of new experimental data. Diagnostic bands are proposed that can discriminate between different fibres from different plants. The contribution of ageing is also considered, demonstrating that sometimes aged fibres cannot be reliably recognised. In contrast, the potential of ATR-FTIR spectroscopy to discriminate between natural and modified fibres is discussed and proven. The best results were obtained when microinvasive ATR-FTIR spectroscopy was coupled with SEM observations. The proposed protocol was tested on microsamples of various cellulosic materials from traditional Japanese samurai armours dating from the 16th to the 20th centuries (Morigi Collection, Museo delle Culture, Lugano, Switzerland). The results facilitated a complete characterisation of the materials and demonstrated that the protocol can be used to study a wide variety of cellulosic materials, including both natural and man-modified fibres, and paper. [ABSTRACT FROM AUTHOR]

Degradation of cellulose in historic manuscripts with iron gall ink leads our heritage to deterioration. Direct aqueous or non-aqueous methods of treatment, which are often used in practice, can damage the authenticity of documents. Therefore, other methods without any wet curative procedures during treatment are in great request. The aim of this work was to evaluate the efficiency of interleaving treatments performed with interleaves containing organic (tetrabuthylammonium bromide and 1-ethyl-3-methylimidazolium bromide) and inorganic (KI and KBr) halide salts on the stability of paper with iron gall ink during ageing. The effect of interleaving was compared with 1) the efficiency of direct treatment of samples and 2) the established conservation procedure-calcium phytate/calcium hydrocarbonate treatment. To evaluate the stabilization effect of different compounds and the efficiency of particular conservation technique measurements of the polymerization degree (viscosimetry, size exclusion chromatography-SEC) and pH were performed before and after accelerated ageing. Colour change in paper samples was determined by reflection measurement using an integrating sphere with a halogen light source. The condition of paper fibers was studied using optical microscopy and scanning electron microscopy (SEM). The tentative results demonstrate that the effective stabilization of paper containing iron gall ink during ageing may successfully be achieved by interleaving using alkaline paper impregnated with KBr. [ABSTRACT FROM AUTHOR]

Utility asset managers and engineers are concerned about the life and reliability of their power transformers which depends on the continued life of the paper insulation. The ageing rate of the paper is affected by water, oxygen and acids. Traditionally, the ageing rate of paper has been studied in sealed vessels however this approach does not allow the possibility to assess the affect of oxygen on paper with different water content. The ageing rate of paper has been studied for dry paper in air (excess oxygen). In these experiments we studied the ageing rate of Kraft and thermally upgraded Kraft paper in medium and high oxygen with varying water content. Furthermore, the oxygen content of the oil in sealed vessels is low which represents only sealed transformers. The ageing rate of the paper has not been determined for free breathing transformers with medium or high oxygen content and for different wetness of paper. In these ageing experiments the water and oxygen content was controlled using a special test rig to compare the ageing rate to previous work and to determine the ageing effect of paper by combining temperature, water content of paper and oxygen content of the oil. We found that the ageing rate of paper with the same water content increased with oxygen content in the oil. Hence, new life curves were developed based on the water content of the paper and the oxygen content of the oil. [ABSTRACT FROM PUBLISHER]

Acid catalyzed ageing of oil impregnated kraft paper has been studied experimentally. Five different carboxylic acids (formic, acetic, laevulinic, stearic and naphtenic acid) have been added to mineral oil to arrive at a neutralization value of 0,4 mg KOH/g. Thereafter, kraft paper of two different humidities has been allowed to equilibrate with the oil. The results show that the lower the molecular weight of the carboxylic acids is the more is absorbed by the paper. Furthermore, a clear synergy for the paper ageing rates between moisture and the lower molecular weight acids is found, while for the higher molecular weight acids almost no effects were found. It is concluded that present techniques for measuring acidity of oils do not reflect these detailed conditions. It is suggested to introduce a new measuring technique for neutralization value where water rinsing is used to identify the content of low molecular weight, water soluble acids. [ABSTRACT FROM AUTHOR]

Abstract: In libraries and archives some of the time-acidified items are so brittle that they cannot be handled without risking loss of material. Currently used deacidification processes do not impart improved mechanical properties to the paper. The use of alcoholic solutions of three different types of aminoalkylalkoxysilanes was studied for the deacidification of paper-based items. It was shown that in addition to deacidifying and improving the stability of papers by providing an alkaline buffer the treatment also significantly improved their mechanical resistance, as measured by the folding endurance and tensile breaking resistance. Essential for the appraisal of the deacidification process, the behaviour upon ageing of the materials treated was investigated. Accelerated ageing methods involving heat/humidity and nitrogen dioxide atmosphere were used separately. It was shown that the reinforcement effect of the three aminosilane compounds tested persisted throughout the ageing, and in one case the mechanical properties even improved after ageing. Two of the aminosilanes tested were studied for their impact at the macromolecular level, on the molar masses of cellulose, using size-exclusion chromatography with multiangle light scattering detection. Their effectiveness in protecting paper from acid hydrolysis occurring during ageing was found significant. [Copyright &y& Elsevier]

Abstract: An optimised headspace-solid-phase microextraction (HS-SPME) coupled with a gas chromatography/mass spectrometry (GC/MS) method has been applied to the analysis of volatile organic compounds (VOCs) emitted from a groundwood pulp book naturally and artificially aged. In order to assess the potentiality of HS-SPME for accessing the compounds produced during the degradation of paper, two different accelerated ageing treatments were applied on an early 20th century book. First, a dry heat ageing was used. Then, the humidity level was increased to take into consideration the role of the hydrolysis reactions in the degradation of paper. The influence of these parameters (temperature and relative humidity) on the reaction products characterized was evaluated separately and discussed. This HS-SPME/GC/MS method associated with accelerated ageing enabled the characterisation of 36 VOCs of which four—furfural, 5-methyl furfural, vanillin and guaiacol—can be considered as relevant carbohydrates and lignin degradation compounds. Their relative abundance has been followed during ageing treatments in order to evaluate their potential role as lignocellulosic degradation markers. HS-SPME/GC/MS appears to be a suitable method for investigating volatile compounds emitted by an old book, and for distinguishing some relevant degradation compounds. Moreover, the method allowed us to monitor their relative abundance. It would now be worthwhile trying to detect these four relevant compounds in naturally aged books using a non-destructive microextraction method and, likewise to suggest a new approach to evaluate the state of deterioration of old books. [Copyright &y& Elsevier]

Abstract: This study concentrated upon refining an in-situ FTIR method to study accelerated ageing of paper under controlled conditions. The standardisation method applying the CH band at 2900cm-1 allowed comparison of different samples from various experiments. To distinguish the features present in the spectra in the carbonyl region coming from carbonyl vibrations not disturbed by water vibrations, bound water present in paper was desorbed and the spectra were recorded at an elevated temperature. An oxidation index of paper defined as a ratio of integrals of bands at 1730cm-1 to that at 1620cm-1 has proved amenable to follow the degradation of cellulose aged under various conditions. The boundary conditions of experiments selected by us were able to discriminate between hydrolysis of glycosidic bonds and oxidation of carbon atoms in a glycopyranose anomer. Following the changes of the spectrum in the carbonyl range proceeding with oxidation time various intermediates of the cellulose partial oxidation were distinguished starting from the least oxidized monocarbonyl groups, through diketones to aldehydes and carboxyls. Assuming a parallel–consecutive mechanism of the cellulose oxidation the spectra were resolved by fitting with multiple Gaussian–Lorentzian functions. [Copyright &y& Elsevier]

Solid-phase microextraction (SPME) coupled to gas chromatography/mass spectrometry (GC/MS) has been applied to the analysis of volatile organic compounds emitted from a naturally aged groundwood pulp paper originating from an old book in order to access the products produced through the decomposition reactions occurring in paper upon ageing. Two different extraction methods were developed and compared: headspace SPME and contact SPME. The influence of few extraction parameters were tested in order to define the best extraction conditions. An optimised non-destructive contact SPME method was elaborated and allowed the characterisation of more than 50 individual constituents. [Copyright &y& Elsevier]