title: Multiple welding of long fiber epoxy vitrimer composites.
abstract: Vitrimers appear as a new class of polymers that exhibit mechanical strength and are insoluble even at high temperatures, like thermosets, and yet, like thermoplastics, they are heat processable, recyclable and weldable. The question arises whether this welding property is maintained in composite materials made of more than 50 vol% of reinforcing fibers. In this paper, we quantitatively analyze the bond strength of epoxy vitrimer-based composite plates made by resin transfer molding and compare them to their non-vitrimer counterparts made of a standard thermoset epoxy. It is demonstrated that only epoxy vitrimer samples show substantial bond strength and the ability to be repeatedly welded thanks to the exchange reactions, which promote improved surface conformity and chemical bonding between the adherands at the joint interface. This opens the way towards joining composite parts without adhesives nor mechanical fasteners.
authors.affiliation: ESPCI-ParisTech, PSL Research University, Matière Molle et Chimie, UMR 7167 CNRS-ESPCI, 10 rue Vauquelin, Paris, 75005, France. francois.tournilhac@espci.fr.
authors.forename: Erwan
authors.initials: E
authors.lastname: Chabert
authors.affiliation: ESPCI-ParisTech, PSL Research University, Sciences analytiques, bioanalytiques et miniaturisation, UMR CBI 8231 CNRS/ESPCI/UPMC, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Vial
authors.affiliation: Institut de Soudure, 18 avenue du Général Patton, BP 50207, F-57506 Saint-Avold Cedex, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Cauchois
authors.affiliation: Institut de Soudure, 18 avenue du Général Patton, BP 50207, F-57506 Saint-Avold Cedex, France.
authors.forename: Marius
authors.initials: M
authors.lastname: Mihaluta
authors.affiliation: ESPCI-ParisTech, PSL Research University, Matière Molle et Chimie, UMR 7167 CNRS-ESPCI, 10 rue Vauquelin, Paris, 75005, France. francois.tournilhac@espci.fr.
authors.forename: François
authors.initials: F
authors.lastname: Tournilhac