Abstract
Magnetic carbonyl iron (CI)-based magnetorheological (MR) fluids generally posses serious dispersion defects due to the large density mismatch between the CI particles and continuous oil medium, which restricts further MR applications. Polymer coating technology has been introduced in an attempt to reduce the density or prevent CI particle aggregation. In this study, a unique functional coating composed of a polyaniline layer and multiwalled carbon nanotube nest was fabricated on the surface of CI particles using a dispersion polymerization and solvent casting method to improve the sedimentation problem of CI-based MR fluids when dispersed in medium oil. The coating morphology was analyzed by scanning electron microscopy. The effect of the functional coating on the MR performance along with the sedimentation observations was investigated using a rotational rheometer. The results showed that the sedimentation of dispersed particles was improved considerably by the reduced density and rough morphology.
References
Bica I (2009) Mater Lett 63:2230
Kim JH, Fang FF, Choi HJ, Seo Y (2008) Mater Lett 62:2897
Li WH, Lynam C, Chen J, Liu B, Zhang XZ, Wallace GG (2007) Mater Lett 60:3116
Ekwebelam CC, See H (2007) Korea-Australia Rheol J 19:35
Pu HT, Jiang FJ, Yang ZL (2006) Mater Lett 60:94
Li WH, Zhang XZ (2008) Korea-Australia Rheol J 20:45
Choi HJ, Jhon MS (2009) Soft Matter 5:1562
Yin J, Zhao X, Xia X, Xiang L, Qiao Y (2008) Polymer 49:4413
Fang FF, Kim JH, Choi HJ, Kim CA (2009) Colloid Polym Sci 287:745
Cheng YC, Guo JJ, Xu GJ, Cui P, Liu XH, Liu FH, Wu JH (2008) Colloid Polym Sci 286:1493
Hong CH, Sung JH, Choi HJ (2009) Colloid Polym Sci 287:583
Bica I, Choi HJ (2008) Int J Mod Phys B 22:5041
See H, Joung C, Ekwebelam C (2007) Int J Mod Phys B 21:4945
Jang IB, Kim HB, Lee JY, You JL, Choi HJ, Jhon MS (2005) J Appl Phys 97:10Q912
de Vicente J, López-López MT, Durán JDG, González-Caballero F (2004) Rheol Acta 44:94
Lim ST, Cho MS, Jang IB, Choi HJ, Jhon MS (2004) IEEE Trans Magn 40:3033
Lim ST, Choi HJ, Jhon MS (2005) IEEE Trans Magn 41:3745
Fang FF, Jang IB, Choi HJ (2007) Diamond Relat Mater 16:1167
Cho MS, Lim ST, Jang IB, Choi HJ, Jhon MS (2004) IEEE Trans Magn 40:3036
Wu WP, Zhao BY, Wu Q, Chen LS, Hu KA (2006) Smart Mater Struct 15:N94
Fang FF, Choi HJ (2008) J Appl Phys 103:07A301
Larson RG (1999) The structure and rheology of complex fluids, Chap. 7. Oxford University Press, New York
Wollny K, Läuger J, Huck S (2002) Appl Rheol 12:25
Gu R, Gong X, Jiang W, Hao L, Xuan S, Zhang Z (2008) J Magn Magn Mater 320:2788
Ginder JM, Davis LC, Elie LD (1996) Int J Mod Phys B 10:3293
Choi HJ, Cho MS, Kim JW, Kim CA, Jhon MS (2001) Appl Phys Lett 78:3806
Fang FF, Choi HJ, Jhon MS (2009) Colloids Surf A: Physicochemical Eng Asp 351:46
Acknowledgment
The authors wish to acknowledge to Mr. Hwang Sun Jae for his valuable assistance with the transmission electron microscopy (TEM) investigations. This work was supported by ETRI (2009).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Fang, F.F., Choi, H.J. & Choi, W.S. Two-layer coating with polymer and carbon nanotube on magnetic carbonyl iron particle and its magnetorheology. Colloid Polym Sci 288, 359–363 (2010). https://doi.org/10.1007/s00396-009-2164-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00396-009-2164-3