Palladium-Mediated Surface-Initiated Kumada Catalyst Polycondensation: A Facile Route Towards Oriented Conjugated Polymers

Authors

  • N. Eric Huddleston,

    1. Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA
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  • S. Kyle Sontag,

    1. Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA
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  • Jenna A. Bilbrey,

    1. Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA
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  • Gareth R. Sheppard,

    1. Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA
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  • Jason Locklin

    Corresponding author
    1. Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA
    • Department of Chemistry and College of Engineering, University of Georgia, Riverbend Research South, 220 Riverbend Road, Athens, Georgia 30602, USA.
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Abstract

Palladium-mediated surface-initiated Kumada catalyst transfer polycondensation is used to generate poly(3-methyl thiophene) films with controlled thickness up to 100 nm. The palladium initiator density is measured using cyclic voltammetry and a ferrocene-capping agent, where the surface density is found to be 55% (1.1 × 1014 molecules per cm2). UV–Vis spectroscopy and AFM show increased aggregation in palladium-initiated films due to the higher grafting density of palladium initiators on the surface. The anisotropy of the P3MT films is determined using polarized UV–Vis spectroscopy, which indicates a degree of orientation perpendicular to the substrate. Evidence that palladium can maintain π-complexation even at elevated temperatures, is also shown through the exclusive intramolecular coupling of both a phenyl and thiophene-based magnesium bromide with different dihaloarenes.

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