title: Solution-Assembled Blends of Regioregularity-Controlled Polythiophenes for Coexistence of Mechanical Resilience and Electronic Performance.
abstract: Considering all the potential applications of organic electronics in portable, wearable, and implantable devices, it is of great importance to develop electroactive materials that possess mechanical reliability along with excellent electronic performance. The coexistence of these two attributes, however, is very difficult to achieve because there is an inverse relationship between the electrical properties and the mechanical flexibility, both of which are associated with the conjugation length and intermolecular ordering of the polymers. Herein, we demonstrate a simple and robust approach based on solution assembly of two different poly(3-hexylthiophene)s (P3HTs) with regioregularity (RR) contents of 97% and 66% to impart both electrical and mechanical properties to films for organic electronic applications. The 97% RR P3HT exhibits high electronic performance but poor mechanical resilience, and vice versa for the 66% RR P3HT. Selective crystallization of high RR P3HT induced by solution assembly allows the use of a one-step process to construct percolated networks of high RR P3HT nanowires (NWs) in a low RR P3HT matrix. Only 5 wt % of high RR P3HT NWs in a 95 wt % low RR P3HT matrix was required to produce hole mobilities comparable to that of pure high RR P3HT, and this blend film exhibited improvements by factors of 20 and 60 in elongation at break and toughness, respectively. Selective self-assembly of RR-controlled polymers allowed us to overcome the fragile nature of highly crystalline conjugated polymer films without sacrificing their electronic properties.
authors.forename: Hyeong Jun
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyeongbuk 37673, Korea.
authors.forename: Moo Yeol
authors.initials: MY
authors.lastname: Lee
authors.forename: Jin-Seong
authors.initials: JS
authors.lastname: Kim
authors.forename: Jae-Han
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyeongbuk 37673, Korea.
authors.forename: Hojeong
authors.initials: H
authors.lastname: Yu
authors.forename: Hongseok
authors.identifier: http://orcid.org/0000-0003-0497-6185
authors.initials: H
authors.lastname: Yun
authors.affiliation: Department of Mechanical Engineering, Khalifa University of Science and Technology , Abu Dhabi 127788, United Arab Emirates.
authors.forename: Kin
authors.initials: K
authors.lastname: Liao
authors.forename: Taek-Soo
authors.identifier: http://orcid.org/0000-0002-2825-7778
authors.initials: TS
authors.lastname: Kim
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyeongbuk 37673, Korea.
authors.forename: Joon Hak
authors.identifier: http://orcid.org/0000-0003-0481-6069
authors.initials: JH
authors.lastname: Oh
authors.forename: Bumjoon J
authors.identifier: http://orcid.org/0000-0001-7783-9689
authors.initials: BJ
authors.lastname: Kim
keywords: mechanical stability; nanowire; regioregularity; solution assembly; stretchable organic electronics