Bio-Inspired Deoxynucleoside-Containing Polymer Networks: Tunable Thermosets and the Influence of Base Pairing

Leveraging the multiple hydrogen bonds of nucleobases in bio-inspired synthetic materials is a powerful strategy toward advanced materials. Here, we report a series of polymer networks derived from the four DNA nucleosides and study the influence of covalent and noncovalent cross-linking on the thermomechanical properties of the resulting materials. The thiol–ene photopolymerization process is modular and robust and has been shown to be compatible with a range of di- and tri-thiols, including bio-derived thiols, as well as nucleoside-derived diene and triene monomers. The presence of complementary bases introduces a secondary noncovalent network that drastically increases the material strength, with the Young’s modulus increasing by up to 25 times compared with that of materials with covalent cross-linking alone. The versatility of the polymerization system can also be exploited to further tune the properties of the resulting hydrolytically degradable polyester thermosets, enabling an ultimate tensile strength of up to 8.3 MPa, an elongation at break of up to 390%, and thermal stability up to 250 °C. The strategy presented here allows access to previously inaccessible regions of the material space for thiol–ene polymer networks and paves the way toward easily accessible and tunable synthetic materials.