화학공학소재연구정보센터
학회 한국고분자학회
학술대회 2004년 가을 (10/08 ~ 10/09, 경북대학교)
권호 29권 2호, p.595
발표분야 기능성 고분자
제목 Improved the dispersion stability of ER fluid based on hollow polyaniline sphere
초록 Electrorheological (ER) fluids comprising polarizable particles suspended in oil have an unusual sensitivity to electric fields, solidifying rapidly when subjected to influence and returning to a liquid state in their absence.1 Many researchers have been conducted for practical utilizations of such suspensions in active control devices such as dampers, shock absorbers, clutches, and brakes, and in new devices including gripping devices, seismic controlling frame structures, human muscle stimulators, and spacecraft deployment dampers.1,2 While this characteristic makes ER fluids valuable in various industrial applications, their long term and quiescent application has been limited because of problems with particle sedimentation. To overcome the sedimentation problem, researchers have proposed several methods, such stabilizing particles by addition of the surfactant, using small particles or high viscosity liquid.3 In this study, we have prepared hollow polyaniline sphere as the disperse phase to solve the sedimentation. The hollow sphere was addressed by synthesizing particles comprising polystyrene coated with polyailine as conducting polymerusing dispersion polymerization and extracted polystyrene from polymer-coated polystyrene. The hollow sphere suspension showed good dispersion stability and ER effect. The sedimentation of prepared ER particle in the silicone oil (50 cS) was observed using UV spectrum. The chemical characteristics of hollow sphere were analyzed by measuring FT-IR, SEM, STEM, particle size analyzer and TGA. And electrical and rheological properties were investigated by measuring current density, conductivity and shear stress using rheometer under various shear rates and electric fields.



Fig. 1. Schematic of overall procedure for preparing hollow polyaniline sphere





Fig. 2. SEM and TEM images of (a) polystyrene, (b) polystyrene-polyaniline, and (c) hollow sphere



References

1. T. Hao, Adv Mater., 13, 1137, (2001)

2. W. M. Winslow, J Appli Phys. 20, 1137 (1949)

3. K. O. Havelka, and J. W. Pialet, Chemtech, June (1996)
저자 성보현1, 고영건1, 최웅수1, 장호겸2
소속 1한국과학기술(연), 2고려대
키워드 ER fluid; polyaniline; hollow sphere
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