Biobased High-Performance Epoxy Vitrimer with UV Shielding for Recyclable Carbon Fiber Reinforced Composites

A novel biobased epoxy vitrimer (Gte-VA) with desirable mechanical properties was synthesized from glycerol triglycidyl ether (Gte) and an imine-containing hardener (VA), which was also a biobased compound from vanillin and 4-aminophenol. The biobased epoxy vitrimer shows Young's modulus of 1.6 GPa and tensile strength of 62 MPa, which is close to the value of amine-cured bisphenol A diglycidyl ether. In addition, it shows excellent reprocessability, recyclability, and UV shielding performance and can be used as a matrix to prepare carbon fiber (CF)-reinforced composites. Based on the amine–imine reversible exchange reaction of the imine bonds, the CF fabric could be recycled without damage from the composite, after degrading the resin in an amine solution. Especially, after recombining the degraded resin with recycled carbon fiber fabric, a regenerated carbon fiber reinforced composite with similar mechanical properties to the original composite can be obtained, achieving full recycling of the carbon fiber reinforced composite. This work will open a door to the development of simple procedures of high-performance biobased epoxy vitrimer and its application in fully recycled carbon fiber reinforced composite.