Despite limited reports employing sustainable solvents for Direct Arylation Polymerization (DArP), the large amount of organic waste generated from conjugated polymer synthesis requires attention. Herein, we report the first emulsion-DArP methodology to afford polymers with molecular weights up to 14.5 kg mol −1 with a 10-fold reduction of organic solvent utilized.
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Tuning the surface energies in a family of poly-3-alkylthiophenes bearing hydrophilic side-chains synthesized via direct arylation polymerization (DArP)
Recent work has identified surface energy as a key figure of merit in predicting the morphology of bulk heterojunction organic solar cells and organic alloy formation in ternary blend organic solar cells. An efficient way of tuning surface energy in conjugated polymers is by introducing functionalised side chains. Here, we present a systematic study on a family of poly(3-hexylthiophene) (P3HT)-based random copolymers bearing five different functionalised side chains (ester, ether, diether, carbamate, nitrile) prepared by direct arylation polymerization (DArP) in terms of their effectiveness in tuning surface energy. This study also exemplifies the superior functional group tolerance in DArP compared to more traditional polymerization procedures. Water droplet contact angle measurements revealed that especially carbamates are highly effective in tuning surface energy, increasing the surface energy from 21.2 mN m −1 with P3HT to 25.5 mN m −1 and 28.6 mN m −1 in 25% and 50% carbamate functionalized copolymers, respectively. Importantly, by introducing a two-carbon-spacer between the conjugated backbone and the functional group, optical and electronic properties of P3HT could be largely maintained in the copolymers as determined by UV/Vis, cyclic voltammetry and space charge limited current hole mobility.
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- PAR ID:
- 10229120
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 12
- Issue:
- 19
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 2840 to 2847
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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