Modification Strategies for Bio-Based Polyurethanes in Flexible Electronic Devices: A Review

Abstract

The escalating environmental crisis and the pursuit of carbon neutrality have driven the development of bio-based polymers as sustainable alternatives to petroleum-derived materials. Flexible electronics require elastomers that integrate mechanical flexibility, processability, and environmental sustainability. Bio-based polyurethanes (BPUs) meet these requirements through strategic molecular designs integrating renewable feedstocks with functional modifications. This review summarizes modification strategies for BPUs, focusing on polyol and isocyanate tailoring, filler incorporation, polymer blending, and surface modification. Their applications in flexible sensors, wearable devices, energy storage, and electronic packaging are highlighted, demonstrating the multifunctional potential of BPUs in next-generation electronics. Challenges including limited electrical and thermal stability, narrow processing windows, and scalability issues are discussed. Future research directions emphasize advanced molecular design, hybrid modification systems, and innovative processing technologies to optimize BPU performance. This review provides theoretical and technological insights for developing sustainable, high-performance materials for flexible electronics.