Solvothermal recovery of carbon fibers from thermoset polymer-based carbon fiber reinforced polymers

Clean, undamaged carbon fibers were easily separated from thermoset epoxy-based carbon fiber reinforced polymers through a two-step solvothermal method by using propanol or benzyl alcohol as solvents. The recovered carbon fibers were characterized by thermal gravity analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical tensile strength tests together with the digital photos. Results show that solvothermal temperature and duration, as well as pretreatment in dichloromethane play important roles in recovering carbon fiber. In addition, the tensile strength of the recovered carbon fibers remains approximately 94.5–98% of virgin carbon fibers.