Isoindigo-Based Binary Polymer Blends for Solution-Processing of Semiconducting Nanofiber Networks

• Published in: ACS applied polymer materials 2019-07, Vol.1 (7), p.1778-1786
• Main Authors: Gumyusenge, Aristide, Luo, Xuyi, Zhang, Hongyi, Pitch, Gregory M, Ayzner, Alexander L, Mei, Jianguo
• Format: Article
• Language: English
• ISSN: 2637-6105; 2637-6105
• DOI: 10.1021/acsapm.9b00321

Molecular self-assembly in isoindigo-based binary polymer blends as a novel platform for facile and robust formation of semiconducting nanofibers is studied. We designed structurally complementary polymers to process all-semiconducting nanocomposites. The selection of the tie-polymer for nucleation and nanofiber formation was probed by tuning crystallinity via side chain engineering. Morphology studies revealed that the crystallinity and the scale-like morphology of the tie-polymer play a crucial role in making long and well stacked nanofiber networks. The optimized blends could be solution-processed into nanotailored semiconducting thin films with no postprocessing steps required. The nanofiber formation in thin films further led to lowered elastic moduli and glass transition but higher crack-on-set strain as well as excellent charge transport properties. The formed nanofibers could also be aligned via a blade-directed shearing method to fabricate organic field-effect transistor devices. Our blending strategy shows to be a promising facile route for processing flexible and stretchable organic semiconducting thin films.