Abstract
Modulating the segmental order in the morphology of conjugated polymers is widely recognized as a crucial factor for achieving optimal electronic properties and mechanical deformability. However, it is worth noting that the segmental order is typically associated with the crystallization process, which can result in rigid and brittle long-range ordered crystalline domains. To precisely control the morphology, a comprehensive understanding of how highly anisotropic conjugated polymers form segmentally ordered structures with ongoing crystallization is essential, yet currently elusive. To fill this knowledge gap, we developed a novel approach with a combination of stage-type fast scanning calorimetry and micro-Raman spectroscopy to capture the series of specimens with a continuum in the polymer percent crystallinity and detect the segmental order in real-time. Through the investigation of conjugated polymers with different backbones and side-chain structures, we observed a generally existing phenomenon that the degree of segmental order saturates before the maximum crystallinity is achieved. This disparity allows the conjugated polymers to achieve good charge carrier mobility while retaining good segmental dynamic mobility through the tailored treatment. Moreover, the crystallization temperature to obtain optimal segmental order can be predicted based on Tg and Tm of conjugated polymers. This in-depth characterization study provides fundamental insights into the evolution of segmental order during crystallization, which can aid in designing and controlling the optoelectronic and mechanical properties of conjugated polymers.
| Original language | English |
|---|---|
| Pages (from-to) | 196-206 |
| Number of pages | 11 |
| Journal | Materials Horizons |
| Volume | 11 |
| Issue number | 1 |
| DOIs | |
| State | Published - Oct 4 2023 |
| Externally published | Yes |
Funding
S. L., Y. L., G. X. and D. Z. are grateful for the support from the National Natural Science Foundation of China (no. 21790345, 22173046, 51673094), Fundamental research funds for the central university (grant no. 020514380274), National Key Research and Development Program of China (grant no. 2020YFA0711504), Shenzhen Science and Technology Innovation Committee (JCY 20200109150656717, JSGG20210629144802007, and JSGG20200103094001790). J. X. acknowledges the support from the University of Chicago on the project of Controlled Organization of Polymeric Solids (PRJ1007197). Z. C., S. Z. and X. G. thanks U.S. Department of Energy, Office of Science, Office of Basic Energy Science under the award DE-SC0022050. Part of the research was conducted at the Center for Nanoscale Materials, a U.S. Department of Energy Office of Science User Facility, which is supported by the U.S. DOE, Office of Basic Energy Sciences, under contract no. DE-AC02-06CH11357. S. R.-G. thank the Natural Science and Engineering Research Council of Canada (NSERC) for financial support through a Discovery Grants (RGPIN-2022-04428). M. U. O. thanks NSERC for financial support through a Canadian Graduate Scholarship (CGSD3-534870-19).