Influence of the Building Unit on Covalent Organic Frameworks in Mediating Photo‐induced Energy‐Transfer Reversible Complexation‐Mediated Radical Polymerization (PET‐RCMP)

Two imine‐based covalent organic framework photocatalysts with different building units, TPB‐DMTA‐COF and TAT‐DMTA‐COF, for photo‐induced energy transfer reversible complexation‐mediated radical polymerization (PET‐RCMP) were developed and investigated, producing ideal polymers with accurate molecular weight and moderate dispersity under visible light irradiation. The chain extension and spatiotemporal control experiments revealed the high chain‐end fidelity of polymers and the compatibility of RCMP processes in both bulk and aqueous system. Moreover, density functional theory (DFT) calculations verified that heteroatom‐doped TAT‐DMTA‐COF exhibits higher activities for weakening C−I bond energy barrier, which promotes PET‐RCMP polymerization performance. This work demonstrates that rational adjustment of building block for constructing COF heterogeneous photocatalyst can enhance the catalytic performance of PET‐RCMP, providing a design methodology for the development of polymeric organic photoelectric semiconductor catalysts to mediate RCMP. Two imine‐based COFs, TAT‐DMTA‐COF and TPB‐DMTA‐COF, were constructed. They served as heterogeneous catalysts for photo‐induced PET‐RCMP under visible light irradiation, realizing efficient polymerization in both oil and aqueous solvent, producing polymers with low molecular weight dispersity and high chain‐end fidelity.