Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Preparation of Al2O3-ZrO2 Composite Powders by the Use of Emulsions: I. Thermodynamic Model of the Emulsion Stability

에멀젼을 이용한 Al2O3-ZrO2 복합분체의 제조 : I. 에멀젼 안정화에 대한 열역학적 모델

  • 한상훈 (연세대학교 요업공학과) ;
  • 백종규 (연세대학교 요업공학과) ;
  • 송승룡 (연세대학교 요업공학과)
  • Published : 1987.06.01
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Abstract

A thermodynamic model to predict the stability of the water-in-oil type emulsion and the size of the droplets in stable emulsions was developed. Using this model, the effects of various factors government the droplet size in the metal salt solution-kerosene-span 80 system for the preparation of Al2O3-ZrO2 composite powders were investigated. It was shown that the given emulsion systems were thermodynamically unstable in every case but could be kinetically meta stable. When radius ofthe droplet was below nm, the increase in entropy change due to the configurational contribution of small droplets dominated the total free energy change for emulsification. The optimum conditions under which smaller deoplet was obtained were proposed and the validity of the model was proved with diameters of the droplet and composite powders experimentally determined.

Keywords

References

  1. Ceramic Bulletin v.60 no.2 Nonconventional Power Preparation Techniques D. W. Johnson,Jr.
  2. Ceramic Processing before Firing Reactive Powders from Solution D. W. Johnson,Jr.;P.K. Gallagher;G. Y. Onoda,Jr.(ed.);L. L. Hench(ed.)
  3. Ceramic Powders The Use of Emulsion in the Preparation of Ceramic Powders P. Reynen;H. Bastius;M. Fiedler;P. Vincenzini(ed.)
  4. Powder Metall. Int. v.8 no.2 Hot Kerosene Drying;A Technique to Prepare reactive Homogeneous Ceramic Powders from Salt Solution P. Reynen;H. Bastius
  5. Better Ceramic through Chemistry Ⅱ Preparation of Ceramic Powders from Emulsions M. Aking;K. Richardson;C. J. Brinker(ed.);D. R. Ulrich(ed.);D. E. Clark(ed.)
  6. J. Chem. Soc. Faraday Trans. v.2 no.71 Stability of Microemulsions E. Ruckenstein;J. C. Chi
  7. J. Colloid Interface Sci. v.53 no.1 Entropy-Induced Dispersion of Bulk Liquids H. Reiss
  8. J. Colloid Interface Sci. v.66 no.2 A Thermodynamic Approach to the Stability of Microemulsions J. E. Crooks
  9. J. Colloid Interface Sci. v.58 no.2 Recent Developments in the Understanding of Colloid Stability J. TH. G. Overbeek
  10. Interfacial Phenomena J. T. Davies;E. K. Rideal
  11. Colloid and Interface Chemistry R. D. Vold;M. J. Vold
  12. Microemulsions-Theory and Practice L. M. Prince(ed.)