Cationic Polyfluorene-b-Neutral Polyfluorene “Rod–Rod” Diblock Copolymers

• Published in: Macromolecules Vol. 45; no. 11; pp. 4441 - 4446
• Main Authors: Gutacker, Andrea, Lin, Chi-Yen, Ying, Lei, Nguyen, Thuc-Quyen, Scherf, Ullrich, Bazan, Guillermo C
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 12.06.2012
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts; Solution polycondensation; Quaternization; Self condensation; Bromine containing copolymer; Photoluminescence; Quaternary ammonium copolymer; Surface topography; Experimental study; Absorption spectrum; Chemical substitution; Thin film; Suzuki coupling; Polyelectrolyte; Organic solution; Monodispersed polymer; Chemical modification; Conjugated copolymer; Preparation; Tertiary amine; Aromatic copolymer; Diblock copolymer; Molecular aggregation; Fluorene derivative copolymer; Successive reaction
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma202738t

All-conjugated “rod–rod” diblock copolymers are an emerging class of polymeric materials of considerable interest for applications in chemical and biological sensors or as components for optoelectronic devices. Here, we report a novel cationic diblock copolymer containing a neutral polyalkylfluorene block covalently bound to a polar polyfluorene counterpartpoly[9,9-bis(6-trimethylammoniumhexyl)-2,7-fluorene]-b-poly(3-hexyl-2,5-thiophene) (PF6NBr-b-PF8)which was synthesized in a sequential Suzuki–Miyaura polymerization and was made ionic with trimethylamine in a subsequent quaternization step. The optical properties of this material were investigated by UV/vis and photoluminescence spectroscopies in three different solvents: methanol, THF and THF/methanol 1:1. Atomic force microscopic (AFM) imaging experiments provided evidence for solvent-induced aggregation. The formation of vesicles and spherical particles is observed in layers from THF and methanolic solution.