Conjugated tootbrush copolymers are prepared by connecting end-capped poly(9,9'-dioctylfluorene) (PF) side-chains (PF) to a poly(3-alkylthiophene) (P3AT) backbone via the CuAAC reaction. The ratio of grafted/nongrafted segment is varied. The influence of the covalent attachment of sidechains to the backbone on the self-assembly is studied by UV-vis spectroscopy. By excitation of the PF side-chains energy transfer to the P3HT backbone is studied.(C) 2017 Elsevier Ltd. All rights reserved.