Ferroelectric Liquid Crystalline Dendrimers:  Synthesis, Thermal Behavior, and Electrooptical Characterization

• Published in: Macromolecules Vol. 34; no. 5; pp. 1221 - 1229
• Main Authors: Busson, P, Örtegren, J, Ihre, H, Gedde, U. W, Hult, A, Andersson, G
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 27.02.2001
• Subjects: acid; Applied sciences; asterisk phase; carbosilane dendrimers; carrying mesogens; Chemical modifications; Chemical reactions and properties; Exact sciences and technology; generation; hyperbranched polyesters; macromolecules; Organic polymers; physical-properties; Physicochemistry of polymers; polarization; polymer; End group; Optically active polymer; Branched polymer; Ester polymer; Thermotropic state; Electrooptical properties; Chiral compound; Experimental study; Ferroelectric properties; Phase transitions; Esterification; Molecular weight property relation; Chemical modification; Ferroelectric materials; Biphenyl derivatives; Liquid crystal polymers; Preparation; Hydroxyl group; Spontaneous polarization; Dendritic structure
• ISSN: 0024-9297; 1520-5835; 1520-5835
• DOI: 10.1021/ma992133e

The preparation and characterization of a series of novel ferroelectric liquid crystalline dendrimers are presented. End-capping of 1-, 2-, and 3-generation dendrimers based on 2,2-bis(hydroxymethyl)propionic acid with mesogens gave surface-functionalized liquid crystalline compounds with 6, 12, and 24 mesogen-containing units, respectively. 4‘ ‘-((R)-1-Methylheptyloxy)phenyl 4-{4‘-[10-(hydroxycarbonyl)decyloxy]phenyl}benzoate was synthesized and used as a mesogen-containing unit. The purity and structure of each compound were determined by 1H NMR spectroscopy, size exclusion chromatography, and elemental analysis. Differential scanning calorimetry and optical microscopy were used to investigate the mesomorphic properties of the mesogen-functionalized dendrimers. The materials displayed a variety of mesophases, including the smectic C* phase. All the liquid crystalline dendrimers showed ferroelectricity, and tilt angle and spontaneous polarization measurements were performed. The obtained results show that the ferroelectric properties of the materials are independent of the generation number of the dendritic scaffold.