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Title: An indacenodithiophene-based semiconducting polymer with high ductility for stretchable organic electronics
An alkyl-substituted indacenodithiophene-based donor–acceptor π-conjugated polymer ( PIDTBPD ) with low stiffness and high ductility is reported. The polymer was synthesized after DFT calculations predicted that it would have a kinked backbone conformation while showing strong intramolecular charge transfer (ICT), suggestive of the fact that it would be beneficial to the polymer's elasticity and charge mobility. Atom-efficient direct arylation polymerization (DArP) was exploited to synthesize the polymer. Mechanical studies indicate that PIDTBPD has relatively rapid stress-relaxation properties, which lead to a low elastic modulus of 200 MPa and high crack-onset strain of ca . 40% (lower limit). A moderate charge carrier mobility of 2 × 10 −3 cm 2 V −1 s −1 with a current on/off ratio of 2.5 × 10 6 was obtained from the fabricated OFETs. Further experiments were performed to elucidate the structural aspects of this polymer: UV-Vis and PL spectra suggest that minimal conformational change occurs in the polymer between its diluted solution and thin film states; DSC measurements indicate that the polymer's T g is below −20 °C, allowing it to be in a rubbery state at room temperature; and XRD studies support this observation suggesting that the polymer is mostly amorphous at room temperature.  more » « less
Award ID(s):
1708317
PAR ID:
10057094
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Polymer Chemistry
Volume:
8
Issue:
34
ISSN:
1759-9954
Page Range / eLocation ID:
5185 to 5193
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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