Buffering the aqueous phase pH in water-in-CO2 microemulsions
Article Abstract:
A study of the effectiveness of various organic zwitterionic (super39-42) and inorganic buffers in raising the aqueous pH phase in both microemulsions and two phase water-CO2 systems to values between 6 and 7 found that the rise in pH from 3 is the result of adding organic and inorganic buffers to nanometer size water-in-CO2 microemulsion droplets stabilized by ammonium perfluoropolyether. The hydrophylic indicates 4-nitrophenyl-2-sulfonate measured the effects of temperature, pressure, buffer type, buffer concentration, ionic strength and CO2 solubility, which were predicted with thermodynamic models. In both Systems, modest buffer loadings resulted in a step pH increase from 2.5 pH units. Further increases in pH required large amounts of base to overcome buffering due to the carbonic acid-bicarbonate equilibrium.
Publication Name: Journal of Physical Chemistry B
Subject: Chemicals, plastics and rubber industries
ISSN: 1520-6106
Year: 1999
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Structure of a triglyceride microemulsion: a small-angle scattering study
Article Abstract:
The microscopic structure of the triglyceride micro emulsion of triolein oil, aqua (water-ethanol, 80/20 wt %) and polyoxyethylene (40) sorbitol hexaoleats has been determined. The aqua and oil in the samples were deuterated to reveal the structures of the aqua, oil and surfactants separately. The results of small-angle neutron scattering showed that the aqueous-surfactant surfaces and the oil-surfactant surfaces have significantly different geometries.
Publication Name: Journal of Physical Chemistry B
Subject: Chemicals, plastics and rubber industries
ISSN: 1520-6106
Year: 1998
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Tricritical points and wetting - nonwetting transitions in nonionic microemulsions
Article Abstract:
When modeling microemulsions, both the nonpolarity of the oil and the strength of the amphiphile should be taken into account as significant parameters. Weakly nonpolar oils need strong amphiphiles to be emulsified, while weak amphiphiles are sufficient for emulsifying strongly nonpolar oils.
Publication Name: Journal of Physical Chemistry B
Subject: Chemicals, plastics and rubber industries
ISSN: 1520-6106
Year: 2000
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