Abstract
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.
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All data supporting the findings of this study are available within the paper and its Supplementary Information.
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Acknowledgements
We acknowledge the High-Performance Computing Platform of Peking University for supporting the computational work. We acknowledge the Molecular Materials and Nanofabrication Laboratory (MMNL) at the College of Chemistry and Molecular Engineering and the Electron Microscopy Laboratory of Peking University for the use of instruments. We thank beamline BL14B1 (Shanghai Synchrotron Radiation Facility) for providing beam time. We thank Mr. Zhuofeng Shi and Dr. Kai Liu from the School of Materials Science and Engineering, Peking University, for constructive advice. We thank Dr. Hui Fu and Dr. Xiu Zhang at the Analytical Instrumental Center of Peking University for their help with solid-state NMR measurement. We thank Mr. Jian’an Liu and Ms. Jinchao Wei at the Analytical Instrumental Center of Institute of Chemistry Chinese Academy of Sciences and Dr. Ying Liu at the Analytical Instrumental Center of Peking University for their help with mass spectrometry analysis. This work is supported by the National Natural Science Foundation of China (22020102001, 22335002), National Key R&D Program of China (2022YFB3602802), and Natural Science Foundation of Beijing Municipality (Z220025).
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X.-Y.Z. and Z.-D.Y. conceived the idea and designed the experiment. Z.-F.Y., J.-Y.W. and J.P. supervised the project. X.-Y.Z., S.-L.L. and W.-Y.H. fabricated the stretchable OFETs. N.-F.L. performed MD simulations. W.S. and X.-Y.W. supervised device fabrication. J.W., X.-Y.Z. and L.Y. performed the FOW test. J.F., X.-Y.Z. and L.Y. performed DMA. Y.-K.Q., Z.-H.X. and Y.-Z.S. supervised material synthesis and characterization. X.-Y.Z. performed all the experiments for materials and devices characterization, and analyzed all the experimental data. C.K.P. helped to visualize experimental data. X.-Y.Z. wrote the whole paper. Z.-F.Y., J.-Y.W. and J.P. reviewed the paper. All the authors gave valuable comments on this paper and confirmed approval of this paper.
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The authors declare no competing financial or non-financial interests. Author Jian Pei is Associate Editor of npj Flexible Electronics. Jian Pei was not involved in the journal’s review of, or decisions related to, this manuscript.
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Zhang, XY., Yu, ZD., Liu, NF. et al. Achieving intrinsically stretchable high-performance n-type semiconducting polymers by tuning side chain ordering inspired by oleic acid. npj Flex Electron (2026). https://doi.org/10.1038/s41528-026-00547-3
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DOI: https://doi.org/10.1038/s41528-026-00547-3
