Publications by authors named "Antonio P Souto"

Polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) dispersed in ethanol, water and water/alginate were used to functionalize untreated and dielectric barrier discharge (DBD) plasma-treated polyamide 6,6 fabric (PA66). The PVP-AgNPs dispersions were deposited onto PA66 by spray and exhaustion methods. The exhaustion method showed a higher amount of deposited AgNPs.

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This research investigated the development of bio-based composites comprising bacterial cellulose (BC), as obtained by static culture, and acrylated epoxidized soybean oil (AESO) as an alternative to leather. AESO was first emulsified; polyethylene glycol (PEG), polydimethylsiloxane (PDMS) and perfluorocarbon-based polymers were also added to the AESO emulsion, with the mixtures being diffused into the BC 3D nanofibrillar matrix by an exhaustion process. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy analysis demonstrated that the tested polymers penetrated well and uniformly into the bulk of the BC matrix.

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In this work, recycled paper sludge (RPS), composed of non-recyclable fibres, was used as a carbon source for bacterial nanocellulose (BNC) production. The biomass was enzymatically hydrolysed with Cellic CTec 2 to produce a sugar syrup with 45.40 g/L glucose, 1.

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Gold nanoparticles (AuNPs), chemically synthesized by citrate reduction, were for the first time immobilized onto chitosan-treated soybean knitted fabric via exhaustion method. AuNPs were successfully produced in the form of highly spherical, moderated polydisperse, stable structures. Their average size was estimated at ≈35 nm.

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This research aimed at producing malleable, breathable and water impermeable bacterial cellulose-based nanocomposites, by impregnating bacterial cellulose (BC) membranes with two commercial hydrophobic polymers used in textile finishing, Persoftal MS (polydimethylsiloxane) and Baygard EFN (perfluorocarbon), by an exhaustion process. These hydrophobic products penetrated the BC membranes and adsorbed tightly onto the surface of the nanofibres, across the entire depth of the material, as demonstrated by Scanning Electron Microscopy and Fourier Transform Infrared spectroscopy studies. The water static contact angles, drop absorption over time and vapour permeability values showed that the composites were impermeable to liquid water but permeable to water vapour.

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In the present work, we investigated the combined effect of poly(styrene-methyl methacrylate-acrylic acid) [P(St-MMA-AA)] PCs with the disperse dye C.I. Disperse Red 343 on the photonic crystals (PCs) shape, distribution, organization, iridescence, chemical structure, thermal stability, and reflectance.

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The structural coloration of a chitosan-coated woven cotton fabric obtained by glutaraldehyde-stabilized deposition of electrostatic self-assembled monodisperse and spherically uniform (250 nm) poly (styrene-methyl methacrylate-acrylic acid) photonic crystal nanospheres (P(St-MMA-AA)) was investigated. Bright iridescent coatings displaying different colors in function of the viewing angle were obtained. The SEM, diffuse reflectance spectroscopy, TGA, DSC and FTIR analyses confirm the presence of structural color and the glutaraldehyde and chitosan ability to provide durable chemical bonding between cotton fabric and photonic crystal (PCs) coating with the highest degradation temperature and the lowest enthalpy.

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This work studies the surface characteristics, antimicrobial activity, and aging effect of plasma-pretreated polyamide 6,6 (PA66) fabrics coated with silver nanoparticles (AgNPs), aiming to identify the optimum size of nanosilver exhibiting antibacterial properties suitable for the manufacture of hospital textiles. The release of bactericidal Ag(+) ions from a 10, 20, 40, 60, and 100 nm AgNPs-coated PA66 surface was a function of the particles' size, number, and aging. Plasma pretreatment promoted both ionic and covalent interactions between AgNPs and the formed oxygen species on the fibers, favoring the deposition of smaller-diameter AgNPs that consequently showed better immediate and durable antimicrobial effects against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria.

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