Effect of degassing on the formation and stability of surfactant-free emulsions and fine teflon dispersions

被引:133
作者
Pashley, RM [1 ]
机构
[1] Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA
关键词
D O I
10.1021/jp026744b
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The results reported here demonstrate that the formation of surfactant-free. oil-in-water emulsions is significantly enhanced by the almost complete removal of dissolved gases. However. in an apparent contradiction, the reintroduction of dissolved gases does not destabilize already formed emulsions, Removal of dissolved gases enables the formation of much more turbid and stable hydrocarbon oil in water emulsions, which can be further studied without the effects of various additives. often needed as stabilizers. The observations reported here suggest that the dispersion of oil droplets in water is opposed by in attractive. hydrophobic force, which is dependent on the presence of dissolved gas, However, once formed, the stability of the emulsions appeared to be unaffected by any attractive hydrophobic force, in either gassed or degassed conditions. Degassing was also found to enhance the dispersion of fine Teflon particles in water.
引用
收藏
页码:1714 / 1720
页数:7
相关论文
共 19 条
[1]   Fluorescence study of the aggregation behavior of different surfactants in aqueous solutions in the presence and in the absence of gas [J].
Alargova, RG ;
Kochijashky, II ;
Zana, R .
LANGMUIR, 1998, 14 (07) :1575-1579
[2]   Role of Co-Ion specificity and dissolved atmospheric gas in colloid interaction [J].
Alfridsson, M ;
Ninham, B ;
Wall, S .
LANGMUIR, 2000, 16 (26) :10087-10091
[3]   CAVITATION AND THE INTERACTION BETWEEN MACROSCOPIC HYDROPHOBIC SURFACES [J].
CHRISTENSON, HK ;
CLAESSON, PM .
SCIENCE, 1988, 239 (4838) :390-392
[4]   Forces measured between latex spheres in aqueous electrolyte: Non-DLVO behavior and sensitivity to dissolved gas [J].
Considine, RF ;
Hayes, RA ;
Horn, RG .
LANGMUIR, 1999, 15 (05) :1657-1659
[5]   THE EFFECT OF ELECTROLYTES ON BUBBLE COALESCENCE IN WATER [J].
CRAIG, VSJ ;
NINHAM, BW ;
PASHLEY, RM .
JOURNAL OF PHYSICAL CHEMISTRY, 1993, 97 (39) :10192-10197
[6]   Direct measurement of hydrophobic forces: A study of dissolved gas, approach rate, and neutron irradiation [J].
Craig, VSJ ;
Ninham, BW ;
Pashley, RM .
LANGMUIR, 1999, 15 (04) :1562-1569
[7]   PHYSICAL CHARACTERISTICS OF ULTRASTABLE LIPID-COATED MICROBUBBLES [J].
DARRIGO, JS ;
IMAE, T .
JOURNAL OF COLLOID AND INTERFACE SCIENCE, 1992, 149 (02) :592-595
[8]  
DARRIGO JS, 1986, STABLE GAS LIQUID EM, V40
[9]  
Hiemenz P. C., 1977, PRINCIPLES COLLOID S
[10]   Attraction between hydrophobic surfaces with and without gas phase [J].
Ishida, N ;
Sakamoto, M ;
Miyahara, M ;
Higashitani, K .
LANGMUIR, 2000, 16 (13) :5681-5687