Dielectric relaxation behavior of ternary systems of water/toluene/Triton X-100: the effects of water and oil contents on microemulsion structure

Chen, Kai; Zhao, Kongshuang

doi:10.1007/s00396-013-3095-6

Cited by 8 publications

(1 citation statement)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dielectric spectra with several dielectric relaxations can be characterized with a set of dielectric parameters by fitting them with a model function including Cole–Cole terms as expressed by eq . , The dielectric parameters include the high-frequency limit of permittivity ε h , the dielectric increment Δε, the relaxation time τ, and the Cole–Cole parameter α (0 < α ≤ 1, indicating the dispersion of the relaxation time), the lower angular symbol i represents the number of dielectric relaxations. In the low-frequency range, the relation between ε dc ″ and the dc conductivity κ l is shown in eq ; ε 0 represents the permittivity of vacuum. ,− ,− ε normald normalc ″ ( ω ) = κ normall ε 0 ω …”

Section: Methods and Theoriesmentioning

confidence: 99%

Dielectric Depiction of 1-Butyl-3-methylimidazolium Tetrafluoroborate/1-Butyl-3-methylimidazolium 1,4-Bis(2-ethylhexyl) Sulfosuccinate/Benzene Microemulsions: Percolation, Interface Polarization, and Electrical Parameters

Li,

Lian,

et al. 2024

Langmuir

View full text Add to dashboard Cite

Two dielectric relaxations located at approximately 10 and 300 MHz were analyzed in the microemulsion composed of the polar ionic liquid (PIL) 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4 ]), the surface-active ionic liquid (SAIL) 1-butyl-3-methylimidazolium 1,4-bis(2-ethylhexyl) sulfosuccinate ([bmim][AOT]), and benzene. The curve of the dc conductivity vs PIL weight fraction shows two inflection points, namely, 16.69 and 27.90 wt %, which are used to divide the PIL/O, bicontinuous (B.C.), and O/PIL subregions. The critical exponents of percolation u = 0.75, 0.79, and 0.80 are suggested from the scaling dependence of dc conductivity on the PIL weight fraction, together with frequency dependences of both permittivity and loss angle, which all infer that static percolation occurs in the microemulsion. Only one dielectric relaxation at high frequency was observed in the PIL/O subregion, when the concentration increased to the boundary between the PIL/O and B.C. subregions; the second dielectric relaxation appeared at low frequency. The high-frequency relaxation is caused by interfacial polarization. The low-frequency relaxation is attributed to the dipole-oriented polarization of AOT − . When the oil content of the system was reduced, the interface became softer to allow more AOT − to rotate, and the cation shifted from moving around its long axis to rotating along its short axis. The static dielectric constant of [bmim][AOT] was given. The dielectric constants and conductivity of the dispersed and continuous phases in the PIL/O and O/PIL subregions were calculated from the dielectric parameters of high-frequency relaxation.

show abstract