Production and Remanufacturing of Vitrimer Matrix Composite Tubes

Composite tubes were filament-wound and cured using a vitrimer epoxy resin and carbon fiber (CF). The matrix was dissolved under mild conditions, and recovered continuous fiber tows were used to rewind a second-generation tube. Property retention and microstructural quality were evaluated by mechanical tests and examination of polished sections. The vitrimer–matrix composite exhibited a higher short-beam shear strength compared to specimens wound with a traditional epoxy, typical of hydrogen tanks. Single-fiber testing revealed that CFs were not degraded by the recycling process. The remanufactured composite exhibited mechanical properties comparable to those of the first-generation material when normalized to the fiber volume fraction. This work demonstrates a circular manufacturing process that includes full fiber recovery and re-use for producing a second-generation filament-wound article.