Intrinsically stretchable conjugated polymer semiconductors in field effect transistors

Stretchable electronics have increasingly gained interest both in the academic and industrial communities owing to its potential to enable a wide variety of applications, especially wearable and implantable devices for biomedical applications. As the key component for electronic devices, the design of a suitable semiconductor is essential, while the solution processability and structural tunability of polymer semiconductor make it a promising candidate. Along this line, it is important to consider the mechanical properties of polymer semiconductors in the design of flexible and stretchable devices placed on soft and curved surfaces to accommodate the constant movement of the human body. However, achieving high mechanical deformability and high charge transport properties simultaneously in polymer semiconductors remains a major challenge. In this trend article, we survey various approaches in designing intrinsically stretchable conjugated polymers, focusing on structure-property relationships from a molecular perspective, such as molecular weight, regioregularity, backbone and side chain modifications. Understanding the influence of these molecular structure parameters on thin film morphology may provide general guidelines for achieving desired microstructures that allow mechanical deformation without interrupting charge transport. Beyond highlighting recent key work in this field, we will discuss future prospects of stretchable conjugated polymers. (C) 2019 Elsevier B.V. All rights reserved.