Abstract
We have developed a carbon fiber reinforced plastic (CFRP) recycling technology using depolymerization of cured epoxy resin (EP) under ordinary pressure. Carbon fiber (CF) was recovered from used tennis rackets by dissolving EP with tripotassium phosphate as a catalyst and benzyl alcohol as a solvent at 200 °C for 10 h. We were able to produce non-woven fabrics with the recovered CF using a carding machine. With these fabrics we then produced recycled CRRPs and measured their mechanical properties. Their properties were nearly equal to the CFRP using commercial fresh CF non-woven fabric. At the same time, the depolymerized EP cured with acid anhydrides was analyzed with high-pressure liquid chromatography and nuclear magnetic resonance. Our results showed that the depolymerization was proceeded by a transesterification reaction to produce dibenzyl esters and bis-phenoxypropanediols, which can be used for recycled EP. We are currently investigating the application of recovered CF and depolymerized EP.
