초록 |
Conventional epoxies are typically used for long term applications such as adhesive, paint, protective layers, etc. However, due to their irreversible network structure, recycling or removal of the end-of-life epoxies are extremely challenging. To address these limitations, reversible epoxies were synthesized by introducing the Diels–Alder reaction using maleimide and furan functional groups. The retro-Diels–Alder (rDA) reaction at a high temperature (> 110 °C) can serve as a recycle process through depolymerization of the epoxy network. Various epoxy precursors were synthesized by manipulating molecular weights, architecture (e.g., 4-arm or 6-arm), and spacers between functional groups. Different stoichiometric ratios between furan and maleimide precursors were examined to control crosslinking density of the reversible epoxy. Thermomechanical behavior of these recyclable epoxies was characterized by calorimetry and rheometry. |