Dramatic Stabilization of a Hexagonal Columnar Mesophase Generated from Supramolecular and Macromolecular Columns by the Semifluorination of the Alkyl Groups of Their Tapered Building Blocks

The tapered building blocks 3, 4,5-tris[(4-(n-decan-l-yloxy)benzyl)oxy]benzoic acid (8-10/0), 3, 4,5-tris[(4-((5, 5,6, 6,7, 7,8, 8,9, 9,10, 10,10-tridecafluoro-n-decan-l-yl)oxy)benzyl)oxy]benzoic acid (8-4/6), 2-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}ethyl 3, 4,5-tris[(4-(n-decan-l-yloxy)benzyl)oxy]benzoate (11-10/ 0), 2-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}ethyl3, 4,5-tris[(4-((5, 5,6, 6,7, 7,8, 8,9, 9,10, 10,10-tridecafluoro-n-decan-l-yl)oxy)benzyl)oxy]benzoate (11-4/6), 2-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}ethyl 3, 4,5-tris(n-decan-l-yloxy)benzoate (18-10/0), 2-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxyjethyl 3, 4,5-tris((5, 5,6, 6,7, 7,-8, 8,9, 9,10, 10,10-tridecafluoro-n-decan-l-yl)oxy)benzoate (18-4/6), the methacrylates of 11-10/0 (12-10/ 0), 11-4/6 (12-4/6), 18-10/0 (19-10/0), and 18-4/6 (19-4/6), and the corresponding polymethacrylates 13-10/0, 13-4/6, 20-10/0, and 20-4/6 weee synthesized and characterized. With the exception of 8-10/0 which forms a smectic mesophase, all other building blocks and polymers self-assemble into tubular supra-molecular architectures which generate hexagonal columnar (Φ_h) mesophases. The fluorination of six out of the ten methylene units of the alkyl tails of these compounds induces a dramatic stabilization of their Φ_h. In the case when the parent hydrogenated compound (8-10/0) forms a lamellar smectic mesophase or only a crystalline phase (18-10/0), fluorination generates a Φ_h mesophase.