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Different pulp samples were irradiated by three energysources:plasma, electron beaming, and γ radiation. The effect of increasedexposure to irradiation was studied by multidetector gel permeationchromatography with fluorescence labeling of carbonyl groups to quantifychanges of the cellulose. Whereas plasma treatment had no effect,for gamma and electron beam the degradation primarily affects thehigh molar mass area. Kinetic calculations based on DPwwere performed. They show close-to-linear relations with slopesin the same order of magnitude, suggesting that wood-derived pulpsdegrade slower than pulps from annual plants. The rise in carbonylgroup content is linear with increasing dose. In particular, in pulpsfrom annual plants, most detected carbonyl structures originate fromthe new reducing end groups. Therefore, oxidative modification ofcellulose molecules by means of radiation appears to be viable forpulps produced from wood. Here the increase in oxidized functionalitiesis partially disconnected from chain scission. [ABSTRACT FROM AUTHOR]

• Solvent-induced degradation depends on both the type of pulp and oxidant. • Hemicellulose-containing pulps more damaged; greater molar mass underestimation. • Amount and position of oxidized groups along the chains affect degradation. • Solvent-induced degradation increases with increasing degree of oxidation. • Lability of peroxide-oxidized celluloses greater than hypochlorite-oxidized ones. The effect of the degradation induced by the solvents for cellulose cuoxam and cadoxen and its dependency on the nature of the carbonyls in oxidatively-damaged cellulosics was investigated by combining a novel approach of sample regeneration and gel permeation chromatography coupled with carbonyl-selective labelling for reliable molecular characterization. The type of cellulosic pulp, degree and mode of oxidation and dissolution time were considered. Results show that the main discriminating factors in determining the degradation of oxidatively-damaged celluloses in alkaline dissolving media are: (1) the type of pulp, i.e. hemicellulose-containing pulps are more severely compromised; (2) of particular relevance, the prior oxidation mechanism, meaning not only the amount of oxidized moieties (greater oxidation, greater solvent-induced damage) but also their position on the chains (i.e. peroxide-oxidized cellulose is more unstable than hypochlorite-oxidized cellulose). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Reducing sugars and calcium-phytate treatments decrease copper in copper-rich inks. • Reducing sugars cause a severe and long-term degradation of both paper and inks. • Both approaches show some post-treatment spreading of metals onto surrounding paper. • Calcium-Phytate protocol provides long-term stabilization of Cu-containing papers. Abstract Iron gall inks are known to be detrimental to the permanence of historic documents. Among the transition metals present, copper is the greatest threat and an open challenge due to the lack of Cu-specific treatments. In this study, we address the inhibition of copper by comparing extraction (a newly proposed glucose-based treatment) vs. chelation (phytate-based) approaches in terms of performances in scavenging copper and slowing the degradation rate, and of possibly induced side effects. Results show that the glucose treatment partially extracts copper, but it causes long-term damages to paper, i.e. increased fragility and discoloration. The phytate protocol was found beneficial in inhibiting the catalytic activity of copper-rich inks. It limits both long-term oxidation and hydrolytic breakdown of samples without compromising the visual appearance. [ABSTRACT FROM AUTHOR]