Intrinsically stretchable polymer semiconductors: molecular design, processing and device applications

Stretchable electronics have received great attention in recent years because they are able to accommodate large mechanical deformation without damage to their electronic properties. These features are highly desirable for novel applications, including wearable devices, health-monitoring electronics, electronic skin, and artificial neural devices. A key factor in the area of stretchable electronics is the development of intrinsically stretchable polymer semiconductors. This review will survey different approaches that can significantly enhance the stretchability of polymer semiconductors without sacrificing their charge-transport properties. To develop stretchable polymer semiconductors, two approaches have been reported: (1) the engineering of the chemical structures of conjugated polymers; and (2) the physical blending of conjugated polymers in an elastomeric matrix. In addition to these two approaches, the influence of the fabrication process (e.g., solution shearing, nanoconfinement, and electrospinning) on the mechanical and electrical properties of polymer semiconductor films is also reviewed. In the final part, we will introduce novel applications of stretchable polymer semiconductors (e.g., electronic skin, artificial neural electronics, and self-healing polymer semiconductors) and the challenges facing these emerging technologies. This review provides a comprehensive introduction to the development of intrinsically stretchable polymer semiconductors covering molecular design, solution processes, and novel applications.