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This dataset is related to the research article entitled ``A fast method to measure the degree of oxidation of dialdehyde celluloses using multivariate calibration and infrared spectroscopy''. In this article, 74 dialdehyde cellulose samples with different degrees of oxidation were prepared by periodate oxidation and analysed by Fourier-transform infrared (FTIR) and near-infrared spectroscopy (NIR). The corresponding degrees of oxidation were determined indirectly by periodate consumption using UV spectroscopy at 222 nm and by the quantitative reaction with hydroxylamine hydrochloride followed by potentiometric titration. Partial least squares regression (PLSR) was used to correlate the infrared data with the corresponding degree of oxidation (DO). The developed NIR/PLSR and FTIR/PLSR models can easily be implemented in other laboratories to quickly and reliably predict the degree of oxidation of dialdehyde celluloses.

The production of paper-based bacterial cellulose-chitosan (BC-Ch) nanocomposites was accomplished following two different approaches. In the first, BC paper sheets were produced and then immersed in an aqueous solution of chitosan (BC-ChI); in the second, BC pulp was impregnated with chitosan prior to the production of paper sheets (BC-ChM). BC-Ch nanocomposites were investigated in terms of physical characteristics, antimicrobial and antioxidant properties, and the ability to inhibit the formation of biofilms on their surface. The two types of BC-Ch nanocomposites maintained the hydrophobic character, the air barrier properties, and the high crystallinity of the BC paper. However, BC-ChI showed a surface with a denser fiber network and with smaller pores than those of BC-ChM. Only 5% of the chitosan leached from the BC-Ch nanocomposites after 96 h of incubation in an aqueous medium, indicating that it was well retained by the BC paper matrix. BC-Ch nanocomposites displayed antimicrobial activity, inhibiting growth of and having a killing effect against bacteria Staphylococcus aureus and Pseudomonas aeruginosa and yeast Candida albicans. Moreover, BC-Ch papers showed activity against the formation of a biofilm on their surface. The incorporation of chitosan increased the antioxidant activity of the BC paper. Paper-based BC-Ch nanocomposites combined the physical properties of BC paper and the antimicrobial, antibiofilm, and antioxidant activities of chitosan.

Màster Oficial de Direcció de Projectes de Conservació-Restauració, Facultat de Belles Arts, Universitat de Barcelona, curs: 2019-2020, Tutor: Ruiz Recasens, Cristina, [spa] El papel por ser higroscópico y dada su composición orgánica es susceptible al deterioro, por ende, resulta de gran importancia saber proceder en cuanto a su correcta conservación-restauración. Uno de los problemas comunes en los materiales de patrimonio celulósico es la presencia de manchas de foxing, las cuales son más ácidas y menos resistentes que el papel circundante. El presente trabajo realiza una revisión de la literatura acerca de los estudios realizados sobre dicha mancha. Varias teorías han surgido intentado dar una explicación a su formación, no obstante, su causa aún no se comprende completamente. Hasta el momento, su formación se ha atribuido a causas bióticas (microbiológicas) y abióticas (metales pesados y/o oxidación). Gracias a esta revisión se pretende conseguir un mayor conocimiento sobre cómo actuar en caso de estar presentes en un sustrato de papel. Para ello, se han recopilado varios estudios acerca de la naturaleza de la mancha, se mencionan técnicas analíticas de las cuales se dispone antes de proceder a su intervención y se sugieren métodos de tratamiento., [eng] Because paper is hygroscopic and given its organic composition, it is susceptible to deterioration, therefore, it is of great importance to know how to proceed with its correct conservation-restoration. One of the common problems in cellulosic heritage materials is the presence of stains from foxing, which are more acidic and less resistant than the surrounding paper. The present work carries out a review of the literature about the studies carried out on this stain. Various theories have emerged that have attempted to explain its formation, however, its cause is not yet fully understood. Until now, its formation has been attributed to abiotic biotic (microbiological) causes (metals and / or oxidation). Thanks to this review, it is intended to obtain a greater knowledge of how to act in the event of these stains being present on a paper substrate. To do this, several studies have been compiled about the nature of the stain, analytical techniques that are available before proceeding with its intervention and treatment methods.

The properties of dialdehyde celluloses, which are usually generated by periodate oxidation, are highly dependent on the aldehyde content, i.e. the degree of oxidation (DO). Thus far, the established methods for determining the DO in dialdehyde celluloses lack simplicity or sufficient speed. More than 60 dialdehyde cellulose samples with varying aldehyde content were analysed by near-infrared and Fourier-transform infrared spectroscopy. This was found to be a reliable method for quickly predicting the DO if combined with partial least squares regression (PLSR). The proposed PLSR models can predict the DO with a high determination coefficient (R2) of 99% when applied to a single pulp type and 94% when applied to multiple types. This new approach quickly and reliably determines the DO of dialdehyde celluloses. It can be easily implemented in everyday research to save money, time and resources, especially because the raw datasets and measured DO are provided.

“This is a post-peer-review, pre-copyedit version of an article published in Cellulose. The final authenticated version is available online at: https://doi.org/10.1007/s10570-019-02678-5 Bacterial cellulose (BC) was functionalized applying the Laccase/TEMPO oxidative treatment, leading to a five-fold increase of the concentration of carboxyl groups. Paper produced with this cellulose showed improved mechanical properties while maintaining barrier function against water and greases as compared to paper produced with non-oxidized BC. Also, the negative charge provided by the carboxyl groups on functionalized BC was used to generate silver nanoparticles (AgNPs), obtaining a BC paper and Ag composite. The presence of AgNPs in the composites was validated by SEM, EDS and ICP analysis, showing spherical, uniformly sized particles stabilized in the BC nanofibers matrix. Additionally, antimicrobial property of composites containing AgNPs was tested. The results showed the strong antimicrobial activity of the composites against Gram-positive and Gram-negative bacteria and fungi. The generation of Ag nanoparticles in a matrix that combine the physical characteristics of the BC nanofibers with the stiffness and the mechanical properties of paper produced composites that may have applicability in technological and biomedical uses