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The recycling of Carbon Fibre-Reinforced Polymers (CFRPs) is becoming increasingly crucial due to the growing demand for sustainability in high-performance industries such as automotive and aerospace. This study investigates the impact of two chemical recycling techniques, chemically assisted solvolysis and plasma-enhanced solvolysis, on the morphology and properties of carbon fibres (CFs) recovered from end-of-life automotive parts. In addition, the effects of fibre sizing are explored to enhance the performance of the recycled carbon fibres (rCFs). The surface morphology of the fibres was characterised using Scanning Electron Microscopy (SEM), and their structural integrity was assessed through Thermogravimetric Analysis (TGA) and Raman spectroscopy. An automatic analysis method based on optical microscopy images was also developed to quantify filament loss during the recycling process. Mechanical testing of single fibres and yarns showed that although rCFs from both recycling methods exhibited a ~20% reduction in tensile strength compared to reference fibres, the application of sizing significantly mitigated these effects (~10% reduction). X-ray Photoelectron Spectroscopy (XPS) further confirmed the introduction of functional oxygen-containing groups on the fibre surface, which improved fibre-matrix adhesion. Overall, the results demonstrate that plasma-enhanced solvolysis was more effective at fully decomposing the resin, while the subsequent application of sizing enhanced the mechanical performance of rCFs, restoring their properties closer to those of virgin fibres. [ABSTRACT FROM AUTHOR]

In this work, a plasma-assisted solvolysis method is proposed as an alternative method for the oxidative degradation of carbon fiber-reinforced composites (CFRCs). Nitrogen plasma ignition within bubbles in a concentrated nitric acid solution is employed, combining the synergistic effects of traditional nitric acid solvolysis and plasma chemistry. A comprehensive process flowchart, including steps such as composite pretreatment, matrix dissolution, fiber recovery and cleaning, solvent regeneration and reuse, and waste treatment, is also discussed, highlighting their importance in process effectiveness. Moreover, a study on the effect of the composite's mass on the plasma-enhanced solvolysis process is conducted, and the results are exploited for the calculation of critical parameters such as efficiency, recovery rates, capacity, fibers quality, energy consumption, consumption of raw materials, operational and installation costs, and environmental impact. A preliminary comparison to other recycling methods based on the literature findings is also attempted, and preliminary metrics to assess the sustainability of the recycling process are proposed. [ABSTRACT FROM AUTHOR]

Transparent polycrystalline TiO 2 thin films have been deposited on unheated glass substrates using RF reactive magnetron sputtering. Depositions were carried out at different glancing angles and with different total gas mixture pressures. The variation of these parameters affected the crystal phase composition and the surface morphology. Depending on the glancing angle and the pressure, rutile, mixed anatase/ rutile and pure anatase were deposited at low substrate temperature. Both hydrophilic and hydrophobic TiO 2 were obtained, exhibiting fast photoconversion to superhydrophilic upon UV irradiation. The effect of the materials physicochemical properties on the wettability and rate of the UV induced superhydrophilicity is evaluated.