Recyclability of ESOF-Ix Materials Enabled by Dynamic Diels-Alder Bonds

The integration of dynamic Diels-Alder bonds into the ESOF-Ix material system facilitated its reusability. As illustrated in Figure 6a, a fragment of ESOF-I1.0 film was subjected to hot pressing at 130℃ and 10 MPa for 1 hour. This resulted in the formation of an intact film devoid of any noticeable defects. The recycling procedure was repeated thrice, followed by tensile testing to assess the efficacy of the recycling process. The stress-strain curves of ESOF-I1.0, depicted in Figure 6a, exhibited consistent patterns after each cycle. Subsequent to three cycles of hot pressing, DSC analysis revealed that the glass transition temperature (Tg) remained largely unchanged in comparison to the original sample. This observation suggests that the crosslinking density remained constant, while the network structure underwent adjustments (Figure 6b). The maintenance of properties in the recycled networks can be attributed to the presence of abundant dynamic Diels-Alder bonds, which enable the rearrangement of the network topology.