Abstract

Polymer semiconductors with inherent stretchability are key materials for the development of stretchable electronics. However, it remains challenging to simultaneously achieve both mechanical stretchability and high charge mobility in polymer semiconductors, primarily due to the rigid nature of polymer backbones. Terpolymers, which contain two types of co-monomer units randomly distributed in the backbones, emerges as a promising solution to this problem. Despite their potential, complex molecular architectures of terpolymers lead to significant variability and limited predictability in their electrical stretchability, hindering the application of this strategy. In this work, we modulated the component ratio of two types of co-monomer units and investigated its impact on the electrical performance of terpolymers under strain by experimental and computational analysis on the morphology evolution and charge transport on molecular scale. Our findings reveal the vital role of extending delocalized frontier orbital for improving the electrical stretchability of terpolymers, which is demonstrated to be tuneable via appropriate backbone engineering.