Reversible and Recyclable Epoxy Vitrimer Based on Covalent Adaptable Networks and Degradabel Disulfide Bonds

초록

Thermoset polymers containing permanently cross-linked networks cannot be remolded and reprocessed after being cured. Vitrimers are a class of thermosets which have plasticity via covalent adaptable networks, so they can be reshaped and reprocessed while maintaining network integrity. Epoxy vitrimers have advantages such as low cost, ease of synthesis and fast stress relaxation at high tempreature. Nevertheless, recycling of epoxy vitrimers is difficult because their degradation is limited due to their internal sturecure composed of tightly cross-linkd networks. Here we synthesized novel epoxy vitrimers which can be recyclable and remendable via the introduction of degradable disulfide bonds. To enhance the strength of mechanical properties, trifunctional epoxy resin was added with bifunctional epoxy. The mechanical and thermal properties were analyzed by theermogravimetric analysis(TGA), differential scanning calorimetry(DSC), dynamic mechanical analysis(DMA) and rheometry.