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Mapping the morphological and nano-mechanical properties of cellulose fibers within paper sheets or textile products at the nano-scale level by using atomic force microscopy is a challenging task due to the huge surface level variation of these materials. However this task is fundamental for applications in forensic or cultural heritage sciences and for the industrial characterization of materials. In order to correlate between nano-mechanical properties and local nanometer scale morphology of different layers of cellulose fibers, a new strategy to prepare samples of isolated cellulose fibers was designed. This approach is based on immobilizing isolated fibers onto glass slides chemically pretreated so as to promote cellulose adhesion. The experiments presented here aim at the nano-scale characterization of fibers in paper samples aged under different external agents (relative humidity, temperature) in such a way as to promote hydrolysis and oxidation of polymers. The observed variability of local mechanical properties of paper fibers was related to varying degrees of cellulose polymerization induced by artificial aging., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Paper is the main component of a huge quantity of cultural heritage. It is primarily composed of cellulose that undergoes significant degradation with the passage of time. By using small angle neutron scattering (SANS), we investigated cellulose's supramolecular structure, which allows access to degradation agents, in ancient and modern samples. For the first time, SANS data were interpreted in terms of water-filled pores, with their sizes increasing from 1.61 nm up to 1.97 nm in natural and artificially aged papers. The protective effect of gelatine sizing was also observed.

We present the results of the first in-depth measurements of the linen cloth of the shroud of Arquata, a precious copy of the Shroud of Turin, which dates back to 1653. The measurements aimed at finding the nature of the faint and low-contrast body impressions on the linen cloth, which are not produced by drawings or paintings as in the other copies of the Shroud of Turin. In general, the optical analysis and the imaging of low-contrast stains on ancient textiles is a complex task, due to the irregular surface and the influence of spectrum, position and uniformity of the illuminating source on colour accuracy and rendition. A correct evaluation requires a multidisciplinary approach. We used noninvasive technologies, including imaging topological radar, laser induced fluorescence, absolute diffused reflectance and absorption spectra, which were previously used to study frescoes, paintings, antique papers, but were never exploited on ancient textiles. The combined results of our measurements and data elaboration allowed identifying the origins of the body impressions, of the stains simulating blood and of the other marks embedded on the linen cloth. Our results can be used to plan the proper long-term conservation of the linen cloth and of marks on it. [ABSTRACT FROM AUTHOR]

This study focuses on the temporal stability of insulation paper used in power transformers and intends to provide reliable and comprehensive estimators for the assessment of paper degradation state. To achieve the objectives artificially aged model papers were investigated along with power transformers insulation papers, by means of Size Exclusion Chromatography (SEC), Fourier-Transform Infrared Spectroscopy (FT-IR), ultraviolet–visible (UV–Vis) reflectance spectroscopy. The results of the UV–Vis analysis were compared to quantum chemical calculations performed by using time-dependent-Density Functional Theory method. The selection of methods allows the assessment of paper degradation state by characterization of depolymerisation progress and development of carbonyl groups. Our results not only are aimed to collect a data basis for paper condition assessment but also to increase the understanding of the mechanism of cellulose degradation in terms of relationship between aging conditions, different degradation paths and its observed effects. • Insulation paper degradation (oxidation and DP changes) described with use of spectroscopic and chromatographic techniques. • Concentration of chromophores in cellulose calculated from the UV–Vis spectra analysed by TDDFT simulations. • Transformer samples described by higher amount of conjugated diketones on C(2) and C(3) atoms than the aged model papers. • Two-indicator OI FTIR and DP approach is superior to one degradation indicator. [ABSTRACT FROM AUTHOR]