Dual-Factor-Controlled Dynamic Precursors Enable On-Demand Thermoset Degradation and Recycling.

Thermosets are well known for their advantages such as high stability and chemical resistance. However, developing sustainable thermosets with degradability and recyclability faces several principal challenges, including reconciling the desired characteristics during service with the recycling and reprocessing properties required at the end of life, establishing efficient methods for large-scale synthesis, and aligning with current manufacturing process. Here a general strategy is presented for the on-demand degradation and recycling of thermosets under mild conditions utilizing dynamic precursors with dual-factor-controlled reversibility.

Cyanurate-Linked Covalent Organic Frameworks Enabled by Dynamic Nucleophilic Aromatic Substitution.

We report, for the first time, highly crystalline cyanurate-linked covalent organic frameworks synthesized via dynamic nucleophilic aromatic substitution. The high crystallinity is enabled by the bond exchange reaction (self-correction) between 2,4,6-triphenoxy-1,3,5-triazine and diphenols via reversible SAr catalyzed by triazabicyclodecene. The CN-COFs contain flexible backbones that exhibit a unique AA'-stacking due to interlayer hydrogen bonding interactions.