X-ray study of oil-microemulsion and oil-water interfaces in ternary amphiphilic systems - art. no. 021601

We present x-ray reflectivity and diffuse scattering measurements from the interfaces between oil-rich and microemulsion bulk phases and between oil-r ich and water-rich phases in three-component microemulsion systems (consist ing of water, alkane, and CiEj, where the last represents n-alkyl polyglyco l 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, varyin g from 25 Angstrom to 160 Angstrom, and the interfacial tension, varying fr om 1.4 mN/m to 0.03 mN/m, for these samples. Although a nonmonotonic profil e at the oil-microemulsion interface is not observed, these measurements ex clude the presence of oscillating profiles with repeat distances greater th en 500 Angstrom.