Enriching an Exchangeable Network with One of Its Components: The Key to High-<i>T</i>_g Epoxy Vitrimers with Accelerated Relaxation

The curing of epoxy-anhydride vitrimers involves anionic copolymerization epoxide and anhydride along with homopolymerization excess epoxide, giving rise to a poly(ester-co-ether) network. By monitoring using infrared spectroscopy in different conditions mapping the presence OH groups, we demonstrate that generation hydroxide necessary for transesterification, exclusively relies on side reactions induced by protic impurities water. To increase yield esters hydroxides, without depressing thermal properties, enrich network one its components, DHEBA (bisphenol A bis(2,3-dihydroxypropyl) ether), potentially available from hydroxylation starting epoxy monomer as well chemical recycling final vitrimer In DHEBA-enriched network, modulus drop associated alpha transition occurs at higher temperatures more steeply than pristine demonstrating better homogeneity together improved heat resistance 3-fold shortened relaxation time throughout 140–180 °C range.