Luminescence quenching study of a percolation transition in a propane/didodecyldimethylammonium bromide/water microemulsion

Journal Article · Thu Nov 25 04:00:00 EST 1993 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100149a038· OSTI ID:5575675

Zhang, J; Fulton, J L; Smith, R D ^[1]

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1. Pacific Northwest Lab., Richland, WA (United States)

Luminescence quenching was used to explore the interdroplet exchange processes for a propane/didodecyldimethylammonium bromide/water microemulsion at a dispersed-phase volume fraction of 0.30. This system shows a percolation type of transition in electrical conductivity as the pressure of the liquid solution is reduced from 450 to 100 bar at 26.5 [degrees]C. Luminescence quenching results are consistent with a system of roughly spherical droplets, with size unaffected by the density of the continuous-phase solvent. However, the intermicellar exchange rate for the quencher is increased by a factor of 3 in the percolation regime. Only part of the increased exchange rate can be attributed to the decrease in the viscosity of the lower density propane, whereas the remainder is attributed to a clustering of the droplets resulting in more effective exchange. Lower propane density increases the strength of attractive interactions between the droplets, leading to extensive clustering and eventual electrical percolation. These results also confirm previous observations indicating that simply altering the strength of interdroplet interactions can induce electrical conductivity percolation. 70 refs., 10 figs., 2 tabs.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5575675
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:47; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400500 -- Photochemistry
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ALKANES
AMMONIUM COMPOUNDS
COLLOIDS
DISPERSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EMULSIONS
HYDROCARBONS
HYDROGEN COMPOUNDS
LASERS
LUMINESCENCE
MATHEMATICAL MODELS
MICROEMULSIONS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
PROPANE
SURFACTANTS
WATER