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Updated: Sep 23, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Constructing Regioregular Star Poly(3-hexylthiophene) via Externally Initiated Kumada Catalyst-Transfer
Mingjian Yuan1, Ken Okamoto1, Hugo A Bronstein1
1Materials Science and Engineering Department, University of Washington, Seattle, Washington 98195-2120, United States.
Abstract:
A synthetic route was developed for the preparation of di- and trifunctional Ni complex-based initiators. Each initiator affords well-defined 2-arm (V-shaped) and 3-arm (Y-shaped) regioregular poly(3-hexylthiophene) (rr-P3HT) with controlled molecular weight and narrow polydispersities by the externally initiated Kumada catalyst-transfer polycondensation. The core spacer length and end o-tolylhalide group of the functional initiators exhibited differences in reactivity and show that the biphenyl spacers are effective for the synthesis of V-shaped and Y-shaped rr-P3HTs.
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