X-ray study of oil-microemulsion and oil-water interfaces in ternary amphiphilic systems.
We present x-ray reflectivity and diffuse scattering measurements from the interfaces between oil-rich and microemulsion bulk phases and between oil-rich and water-rich phases in three-component microemulsion systems (consisting of water, alkane, and C(i)E(j), where the last represents n-alkyl polyglycol ether with i=4,6,10 and j=1,2,4). The x-ray measurements are analyzed with a two-parameter fit that determines the interfacial roughness, varying from 25 A to 160 A, and the interfacial tension, varying from 1.4 mN/m to 0.03 mN/m, for these samples. Although a nonmonotonic profile at the oil-microemulsion interface is not observed, these measurements exclude the presence of oscillating profiles with repeat distances greater then 500 A.
Mitrinović
D M
DM
University of Illinois at Chicago, Department of Physics, 845 West Taylor Street, Chicago, Illinois 60607, USA.
Williams
S M
SM
Schlossman
M L
ML