title: Positive and negative electrorheological response of alginate salts dispersed suspensions under electric field.
abstract: Electrorheological (ER) effects of alginic acid and alginate salts (Na(+) alginate, NH(4)(+) alginate, and Ca(2+) alginate) dispersed suspensions were investigated under DC electric fields. A noteworthy result is that the Ca(2+) alginate dispersed suspension showed negative electrorheological effects under electric fields while the other suspensions exhibited positive electrorheological effects. It is the first time that the negative ER effect is obtained with the biomacromolecule. Interestingly, at the DC electric fields, the electromigration of particles to two electrodes was observed in the negative ER fluid, while the particles-bridges formed between two electrodes in the case of the positive ER fluid. In conclusion, the specific salt type of biomacromolecules could be suitable ER particles for negative ER suspension. We believe that our study can present a new way for the development of the biocompatible and eco-friendly negative ER fluids.
authors: Center for Urban Energy Systems, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Korea.
authors: Young Gun
authors: YG
authors: Ko
authors: Hyun Jeong
authors: HJ
authors: Lee
authors: Yong Jin
authors: YJ
authors: Chun
authors: Ung Su
authors: US
authors: Choi
authors: Ki Pung
authors: KP
authors: Yoo