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This paper focuses on investigating the use of low-pressure oxygen plasma as a surface treatment aimed at enhancing the wettability and dyeability of cotton fabrics for use in textiles and footwear materials. Plasma activation modified the cotton fabric surfaces, increasing their affinity for polar liquids. The research thoroughly characterised the treated fabrics through a combination of analytical methods and physical testing. Plasma treatment was performed using a 13.56 MHz RF generator at 90 W power, with an oxygen flow rate of 500 sccm and a pressure of 0.30 mbar, for treatment durations of 30, 60, and 120 s. Changes in surface chemistry were analysed with XPS, while SEM was used to observe morphological changes. Static water contact angle measurements confirmed a reduction from 128.5° in untreated cotton to 25.6° in samples treated for 30 s, indicating a significant increase in hydrophilicity. Water absorption tests showed a maximum absorption capacity of 119.6% after 60 min for plasma-treated samples, compared to 65.7% for untreated cotton. Contact angle measurements verified that surface hydrophilicity increased following the treatment. Furthermore, physical tests, such as rub fastness, colourimetry, and water absorption, were carried out to evaluate improvements in wettability, dyeability, and overall performance. The results showed notable enhancements in the wetting properties of cotton textiles, enabling better absorption of water and dyes, along with improved fixation. The comprehensive characterisations provided insights into the mechanisms behind these improvements. This research offers a sustainable approach for the textile industry, as plasma technology is a dry process that enhances dyeing efficiency while maintaining fabric performance and lowering environmental impact. [ABSTRACT FROM AUTHOR]

Advances in cleaner technologies have a critical role in reaching Europe's climate and environmental goals. More precisely, in the case of the footwear bonding process its environmental impact is mainly related to the VOCs emissions resulting from the use of organic solvents in the most common adhesives used, as well as during the application of some surface treatments such as halogenation. Moreover, the use of raw materials of fossil origin also contributes to its carbon footprint. The aim of this work is to deploy cleaner technologies to minimise the environmental footprint of the footwear bonding process through several approaches at different steps of the process life cycle, also to contribute to footwear circularity. This work focuses on the synthesis and application of reactive hot melt polyurethanes from CO2-based polyols as biobased adhesives, and the study of plasma-based surface treatments (low-pressure plasma and atmospheric pressure plasma) to improve adhesion properties, using styrene-butadiene vulcanised (SBR) rubber as a representative footwear soling material. The influence of CO2-based polyols on the polyurethane structure and the physicochemical effects of the plasma treatments on the rubber surface, as well as the final adhesion properties have been evaluated by means of different experimental techniques. The results showed that the values obtained for the T-peel strength of the adhesive joints studied, with the combination of the application of the plasma surface treatments and the biobased reactive hotmelt, exceed the minimum quality requirements for footwear according to the standardised tests. As a result, the deployment of such cleaner technologies regarding adhesives and surface treatments in the footwear bonding process will contribute to improving footwear carbon footprint and its circularity. [ABSTRACT FROM AUTHOR]