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Abstract Recent work on non‐conjugated pendant electroactive polymers (NCPEPs) has demonstrated significant impacts of structural parameters such as backbone stereoregularity and the spacer connecting the pendant to the backbone on properties, most notably on charge carrier mobilities. Tuning of the pendant group however has not been reported for stereoregular NCPEPs. Here we present a family of novel isotactic poly((carbazolyl‐alkyl‐triazolyl)methyl methacrylates) (PCzATMMAs) for which the effects of increasing the pendant group from carbazole to 3,6‐bis(4‐(2‐ethylhexyl)thiophen‐2‐yl)‐carbazole were investigated. Based on unsuccessful post‐polymerization functionalization with this extended group via previously reported transesterification and thiol‐ene methodologies, we report functionalization via copper‐catalyzed azide‐alkyne cycloaddition which was demonstrated to be highly effective. The effect of spacer length was also investigated for comparison with previously established effects with alkyl spacers. Within the family of PCzATMMAs, hole mobilities were found to increase with longer spacer length and with thermal annealing. The incorporation of an extended pendant with alkyl solubilizing chains was found to result in a lower hole mobility than the equivalent polymer with an unfunctionalized pendant group. Importantly, the copper catalyzed azide‐alkyne cycloaddition proved to be an effective method of post‐polymerization functionalization for stereoregular NCPEPs when extending beyond a simple carbazole pendant.
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Functionalized anthrathienothiophenes: synthesis, properties, and integration into OFETs
For more than two decades, the silylethyne functionalization scheme has been used to induce strong π-stacking interactions in linear acenes and heteroacenes. As part of our efforts to better understand the crystal engineering aspects of silylethyne functionalization, along with an interest in studying the impact of ring topology on the electronic and optical properties of heteroacenes, we describe here the integration of thieno[3,2- b ]thiophene (a non-linear isomer of the well-known anthradithiophene) into our well established crystal engineering scheme. By utilizing the thienothiophene moiety coupled with an asymmetric solubilizing group (isopropenyldiisopropylsilylethyne), we were able to achieve charge carrier mobilities ( μ ) upwards of 0.22 cm 2 V −1 s −1 . Based on their increased stability and promising initial mobilities, the use of this thienothiophene moiety may offer a new approach to the formation of larger heteroacene analogues with more than 5 aromatic rings.
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- Award ID(s):
- 1849213
- PAR ID:
- 10410814
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 10
- Issue:
- 39
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 14439 to 14443
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2TC02977D
