Enhanced Benzothiadiazole-Based Polymer Materials: Introducing Self-Healing and Stretchability through Nature-Inspired Hydrogen Bonding

Inspired by the fundamental role of hydrogen bonding in natural processes, such as the formation of DNA’s double helix and the unique properties of water, this research explores the incorporation of urea side chains in a conjugated polymer to harness their benefits in developing stretchable and self-healing polymers suited for applications in organic field-effect transistors (OFETs). A conjugated polymer intended for use in OFETs was synthesized, employing a Stille reaction involving two distinct benzothiadiazole (BT) monomers: 10% incorporated with a C16 chain and 90% featuring a urea functional group. These were polymerized in a 1:1 ratio with an IDTT monomer. OFETs, known for their low cost, easy fabrication, and flexibility, are crucial for the development of large-area electronic devices like electronic skin. Drawing inspiration from nature, where hydrogen bonding plays a pivotal role in processes like the double-helix formation in DNA and the properties of water, the conjugated polymer utilizes urea side chains to induce hydrogen bonding. This promotes molecular self-assembly into a well-ordered, planar structure in the solid state, facilitating efficient π-π stacking interactions between the aromatic rings of the polymer, thereby optimizing the rate of electron transfer. Notably, this nature-inspired hydrogen bonding not only enhances tensile strength and maintains electrical performance but also introduces self-healing capabilities to the polymer. The dynamic, reversible bonds allow for autonomous repair, realigning polymer chains, and enhancing material resilience. The unique attributes of this polymer make it particularly well-suited for enhancing the efficiency and longevity of OFET applications.