X-Ray Photoelectron-Spectroscopic Studies of Carbon Fiber Surfaces. Part XII: The Effect of Microwave Plasma Treatment on Pitch-Based Carbon Fiber Surfaces

X-ray photoelectron spectroscopy has been used to monitor the surface chemical changes on DuPont high-modulus pitch-based carbon fiber surfaces brought about by microwave air-plasma treatments for different periods of time. The air-plasma treatment increased the fiber surface functionalities, but extended treatment caused fiber damage. X-ray diffraction studies showed that the bulk structure was not affected by the air-plasma treatment. XPS valence band spectra proved a more sensitive probe of the surface chemistry of the carbon fibers than XPS core studies. Air-plasma treatment of fibers promises to be an effective method of fiber treatment.