Surface Modification of Recycled Carbon Fibers by Use of Plasma Treatment
In this study, sized and thermally desized virgin carbon fibers (vCF) as well as recycled carbon fibers (rCF) from a thermal recycling process are plasma treated by a plasma-jet. The effect of two different process gases (nitrogen and dinitrogen monoxide) and the influence of the distance between the plasma source and the fiber surface are studied with the aim of increasing the oxygen and nitrogen concentration on the rCF surfaces. Higher surface coverage of oxygen-and nitrogen-containing functional groups is supposed to lead to a better adhesion between the carbon fiber and the epoxy resin matrix. The elemental compositions and functional groups of the treated carbon fiber surfaces are studied by x-ray photoelectron spectroscopy. The effect of plasma treatment on the fiber properties like tensile strength, tensile modulus and surface roughness is investigated.