Electrorheological Property of Rare Earth Complexes Based on β-Cyclodextrin Inclusion

The rare earth (RE) complexes based on β-cyclodextrin (β-CD) inclusion, β-CD-PTA-RE (RE = Y, Gd, Er, La), as a new class of electrorheological (ER) material, were synthesized by a very simple grinding method. The nontoxic and facile β-cyclodextrin (host), as well as p-toluenesulfonic acid (PTA, guest) and RECl3 or Y(NO3)3 were chosen as starting materials. The effects of different RE ions and RE content on the ER property of the materials were studied. The results showed that the ER performance of β-CD-PTA-Y(NO3)3 complex with a β-CD:PTA: Y(NO3)3 molar ratio of 1:2: 0.2 was the best. The Y(NO3)3 was more effective than the YCl3 in heightening ER activity of the inclusion material. The dielectric property played an important role in influencing ER property of a material.