Epoxy Homopolymerization as a Tool to Tune the Thermo-Mechanical Properties and Fracture Toughness of Vitrimers

Epoxy/dicarboxylic acid vitrimer was prepared by the solvent-free reaction of diglycidyl ether bisphenol A (DGEBA) and 1,4-cyclohexane dicarboxylic (CHDA) with addition monobutyltin oxide (Sn) as a catalyst. By tailoring catalyst content (?5 mol %), an effective conversion functional groups during cure demonstrated network polymerization mechanisms sequence side reactions. Indeed, manufactured vitrimers exhibit creep full stress relaxation thanks to catalytic transesterifications. changing epoxy/diacid ratio, thermo-mechanical properties mechanical behavior epoxy/acid can be tuned while keeping self-healing ability. At high epoxy excess, both glass-transition temperature (Tg) solid–liquid viscoelastic transition (Tv) shift higher temperature. formulations 1:0.6 1:0.5 (epoxy/acyl), remarkable improvement fracture toughness (KIc) is observed, indicating from stiff relatively ductile materials at 1:0.6. This attributed altered structures due etherification homopolymerization. The rough surface suggests more energy dissipation crack propagation in excess epoxy. After healing, welded still good only slight reduction (<10%) KIc. We believe that these are promising matrices composite fields.