D. Marsitzky

Optimisation of polyfluorenes for light emitting applications

The properties of polyfluorenes for use in luminescent devices have been improved by a variety of approaches. Their conjugation length may be extended by using more planar indenofluorene units. Formation of long wavelength emitting aggregates is suppressed by attachment of bulky dendron groups to give stable blue emission. The emission colour can be tuned across the visible spectrum by incorporation of perylene dye units on the main chain or as substituents. Rod-coil copolymers have been made in order to achieve control of the supramolecular order. Polyfluorenone prepared by a precursor route shows improved electron injection and transport properties.

Highly Regular Organization of Conjugated Polymer Chains via Block Copolymer Self-Assembly

The microscopic organization in thin films of block copolymers containing either polyparaphenylene, or polyphenyleneethynylene rigid segments covalently bound to a flexible polydimethylsiloxane or polystyrene sequence was investigated. Atomic force microscopy and theoretical modeling based on molecular mechanics/molecular dynamics calculations were combined. The typical morphology obtained revealed the presence of bright elongated structures.

Synthesis of rod‐coil block copolymers via end‐functionalized poly(p‐phenylene)s

This paper describes a new way to synthesize rod-coil block copolymers consisting of poly(p-phenylene) (PPP) as rigid rod and either polystyrene (PS) or poly(ethylene oxide) (PEO) as flexible coil. The Suzuki-coupling of the AB-type monomer 4-bromo-2,5-diheptylbenzeneboronic acid (1) under strictly proton-free conditions leads to the control of PPP endgroups and hence allows the synthesis of a variety of differently end-functionalized poly(p-phenylene)s. The poly(2,5-diheptyl-p-phenylene)-block-polystyrene (7) is then prepared via condensation via condensation of anionically polymerized living polystyrene (6) with α-(4-formylphenyl)-ω-phenyl-poly(2,5diheptyl-p-phenylene) (4). Toluenesulfonic acid catalyzed condensation of α-methyl-ω-amino-poly(oxyethylene) (8) with PPP 4 yields poly(2,5-diheptyl-p-phenylene)-block-poly(ethylene oxide) (9).

Organization of Conjugated Polymer Materials via Block Copolymer Self-Assembly

The morphology of thin films of diblock rod-coil copolymers containing one conjugated segment and one non-conjugated segment is analyzed with a combination of atomic force microscopy data and molecular mechanics/dynamics calculations. The copolymers organize as very long, thin objects with constant width and height in the nanometer range.