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Although high-temperature operation (i.e., beyond 150°C) is of great interest for many electronics applications, achieving stable carrier mobilities for organic semiconductors at elevated temperatures is fundamentally challenging. We report a general strategy to make thermally stable high-temperature semiconducting polymer blends, composed of interpenetrating semicrystalline conjugated polymers and high glass-transition temperature insulating matrices. When properly engineered, such polymer blends display a temperature-insensitive charge transport behavior with hole mobility exceeding 2.0 cm 2 /V·s across a wide temperature range from room temperature up to 220°C in thin-film transistors.
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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.
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- Award ID(s):
- 1708317
- PAR ID:
- 10057094
- 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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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/C7PY00435D
