Achieving intrinsically stretchable high-performance n-type semiconducting polymers by tuning side chain ordering inspired by oleic acid

While p-type intrinsically stretchable conjugated polymers have seen substantial progress, their n-type counterparts still exhibit substantially inferior performances. This work demonstrates the enhancement of the mechanical performances of high-mobility n-type conjugated polymers by tailoring side chain order, inspired by the molecular characteristics of oleic acid and stearic acid. With additional increasing side chain disorders resulting from the cis-configuration of the olefin structure, the tensile modulus of polymer films is reduced, and the crack-onset strain limits are increased. Accordingly, we successfully developed an intrinsically stretchable n-type polymer that retains high electron mobilities of ~0.4 cm2 V−1 s−1 under 50% strain or after 2000 stretching-releasing cycles at 25% strain. Furthermore, we investigate how polymer chain rearrangement influences the dynamic behavior of these polymers. Their stretchability is attributed to multiscale chain alignment during deformation, revealing a clear structure–performance relationship at the molecular level. In summary, our side-chain engineering approach provides a valuable design strategy for developing high-performance stretchable n-type conjugated polymers.