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Preparation of transparent and superhydrophobic coatings by co-deposition of an aqueous solution of an amphiphilic fluorinated block copolymer (FBC) with silica particles was developped. Spin-coating of this aqueous solution onto glass followed by an appropriate thermal treatment promotes the self-assembly of the hybrid material with the formation of superhydrophobic, robust and transparent coatings.

To explore the effectiveness of monofluorinated isoindigo as an electron-deficient building block in push-pull conjugated polymers for organic solar cell applications, four low bandgap copolymers are effectively synthesized and characterized. The effects of fluorine introduction, thiophene spacer length and polymer molar mass on the general electro-optical polymer characteristics, thin film blend microstructure and electronic performance are investigated. Isoindigo monofluorination effectively improves the power conversion efficiency from 2.8 up to 5.0% upon molar mass optimization, without using any processing additives or post-treatments.

We report on a simple process for the chemisorption of poly(thiophene)-based block copolymers onto ITO substrates. Two poly(thiophene) block copolymers functionalized by acrylates on the second block are prepared by the Grignard Metathesis (GRIM) process. The first block is composed of poly(3-hexylthiophene) (P3HT) and the second block is either a polythiophene bearing an acrylate group on each monomer unit (PAcET), or a polythiophene bearing both acrylate and poly(ethylene glycol) side chains (P(AcET-co-PEGET)). After characterizing their macromolecular parameters and optical properties, we investigate their ability to self-assemble into micelles in DMF solutions. This solvent is required for the electrografting procedure that is used for strongly anchoring the polymer to ITO. These micelles are expected to be formed by a P3HT core and a PAcET or P(AcET-co-PEGET) shell. When PEG side chains are present in the second block, the copolymer nicely self-assembles into micelles decorated by acrylates. Cathodic polarization of ITO induces chemisorption and polymerization of acrylate groups, leading to an adherent organized film of poly(thiophene)-based micelles. The optical absorption spectra show that the electrografted polymer chains have a degree of π-electron conjugation similar to that of crystalline P3HT films. In the absence of the PEG chains, the copolymer does not organize into micelles, due to the low stabilizing ability of the second block in DMF.