Molecule-based electrorheological material, a β-cyclodextrin derivative and its rare earth complexes

Molecule-based electrorheological (ER) materials as a novel type of ER materials, dicarboxylic acid [H-2(beta-CD-A)] of beta-cyclodextrin (beta-CD) and the rare earth (RE) complexes [(beta-CD-A)(3)(RE)(2)] (RE=Y, La, Gd) materials, were synthesized, the ER performance and dielectric property of the materials were studied. Our results show that these molecule-based ER materials exhibit clear ER effect. The ER performance of beta-CD can be enhanced with the formation of H-2(beta-CD-A) and RE complexes. The ER activity of the yttrium complex is the highest among these RE complexes. The dielectric property plays an important role in influencing the ER property of these materials. (C) 2008 Elsevier B.V. All rights reserved.