Carbon fibre fluorination: Surface and structural properties

Jean-Charles Agopian (1) , Olivier Téraube (2) , Karine Charlet (1) , Samar Hajjar-Garreau (3) , Elodie Petit (2) , Nicolas Batisse (2) , Marc Dubois (2)

1 IP - Institut Pascal
2 ICCF - Institut de Chimie de Clermont-Ferrand
3 IS2M - Institut de Science des Matériaux de Mulhouse

Knowing that carbon fibre reinforced polymers are sensitive to moisture through their interphases, carbon fibres sized with Bisphenol A diglycidyl ether were fluorinated under a N2/F2 atmosphere, which confers them a hydrophobic behaviour, as highlighted by wettability measurements. Low fluorination temperatures (< 230°C) lead to a sizing perfluorination and even overfluorination without carbon fibre fluorination, while higher temperatures (> 250°C) result in a carbon lattice fluorination with a complete desizing of the fibre through decomposition, that has been evidenced through X-Ray Diffraction and Raman spectroscopy studies. For both fluorination mechanisms, 19F Nuclear Magnetic Resonance, X-Ray Photoelectron and infrared spectroscopies have been used to study the nature of fluorine bonds. Scanning Electron Microscope and Energy-Dispersive X-Ray Spectroscopy have evidenced a core–shell structure for the fluorinated fibres with a fibre degradation at the highest temperatures, also highlighted by tensile tests, Atomic Force Microscopy and Electron Paramagnetic Resonance.

Mots clés: Fluorination; Carbon fibers; Surface and Bulk Properties; XPS; Wettability

Domaines: Matériaux; Mécanique des matériaux [physics.class-ph]

Jean-Charles Agopian, Olivier Téraube, Karine Charlet, Samar Hajjar-Garreau, Elodie Petit, et al.. Carbon fibre fluorination: Surface and structural properties. Applied Surface Science, 2022, 595, pp.153561. ⟨10.1016/j.apsusc.2022.153561⟩. ⟨hal-04497941⟩