Tetrazine Dynamic Covalent Polymer Networks

Abstract

Dynamic nucleophilic aromatic substitution of tetrazines (SNTz) has been used for the synthesis of dynamic covalent polymer networks that take advantage of both the reversible nature of the reaction and the versatility of the tetrazine ring. Polymer microspheres were easily synthesized and they were proved to be degraded either by UV irradiation or by a chemical stimulus, recovering the original monomer, which allows an efficient recycling. It was also possible to convert one polymer into another one (metamorphosis) by irreversible exchange of monomers. Additionally, the backbone of the polymers could be reduced/oxidized or postfunctionalized with polar groups by the inverse electron demand Diels–Alder (IEDDA) reaction, which not only locked the exchange but also allows for the modulation of the polymer properties, such as solubility in water. Tetrazine dynamic polymers are a recyclable and highly versatile kind of material that enables postsynthetic modulation of their properties as well as provides novel chemical methods and photodegradation.