Effect of plasma surface treatment of recycled carbon fiber on carbon fiber-reinforced plastics (CFRP) interfacial properties

•Plasma treatment was used to improve the adhesion property between the recycled CF and polymer matrix.•In order to evaluate the adhesion between plasma treated recycled CF and polymer, micro droplet test was conducted.•The interfacial shear strength and the interfacial adhesion of recycled carbon fiber increased. We studied the effects of plasma surface treatment of recycled carbon fiber on adhesion of the fiber to polymers after various treatment times. Conventional surface treatment methods have been attempted for recycled carbon fiber, but most require very long processing times, which may increase cost. Hence, in this study, plasma processing was performed for 0.5s or less. Surface functionalization was quantified by X-ray photoelectron spectroscopy. O/C increased from approximately 11% to 25%. The micro-droplet test of adhesion properties and the mechanical properties of CFRP were also investigated.