Dielectric relaxation in sodium bis(2-ethylhexyl)sulfosuccinate–water–decane microemulsions near the percolation temperature threshold

Feldman, Yuri; Kozlovich, Nick; Nir, I.; Garti, Nissim

doi:10.1103/physreve.51.478

Cited by 104 publications

(93 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…37,38 For bulk 5CB, however, the charge carrier should be small ionic impurities. Therefore, the higher E dc and larger σ dc in LCMs as compared with those of bulk 5CB should be due to the larger size and higher concentration of the charge carrier, respectively.…”

Section: B 5cb/ddab/water Microemulsion: Dielectric Spectra and DC Cmentioning

confidence: 99%

See 1 more Smart Citation

Does transparent nematic phase exist in 5CB/DDAB/water microemulsions? From the viewpoint of temperature dependent dielectric spectroscopy

Chen

Nozaki

2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

Liquid crystal colloids have received tremendous attention because of its great potential both in the understanding of the liquid crystalline phase and in searching for new application of liquid crystals. Inverse microemulsion composed of 4-cyano-4-n-pentylbiphenyl (5CB), didodecyl dimethyl ammonium bromide, and water was investigated by means of broadband dielectric spectroscopy in this study. Based on the understanding of previous investigations on the same system, the isotropic phase was taken into account to quantitatively characterize the bulklike relaxations after the isotropic-tonematic phase transition. Analogous results concerning the phase transition and phase composition to other investigations were obtained. In addition to bulklike relaxations, a new relaxation was observed at the frequency range about two orders lower than bulklike relaxations. This new relaxation shows abnormal temperature dependence, suggesting that superstructures composed of water droplets and confined 5CB molecules exist. This superstructure possibly possesses a confined nanoscaled liquid crystal ordering and may correspond to the notion of the transparent nematic phase.

show abstract

Section: B 5cb/ddab/water Microemulsion: Dielectric Spectra and DC Cmentioning

confidence: 99%

“…However, the rotational diffusion of the whole water droplet may contribute to the slow process. The corresponding relaxation time is given by 38,45 …”

Section: Cb/ddab/water Microemulsion: Slow Processmentioning

confidence: 99%

Does transparent nematic phase exist in 5CB/DDAB/water microemulsions? From the viewpoint of temperature dependent dielectric spectroscopy

Chen

Nozaki

2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…23 Obvious dielectric relaxation is observed only above 1 GHz for the mixtures, which is assigned to the dynamics of water molecules including bulk-like (free) water and hydration water. However, relaxations due to the dynamics of micelles 13,27 and due to the radial and tangential diffusion of ions in the micelle/solution interface 15,28 are not observed, although these relaxations have been observed in many micelle solutions. Our measurement results of TX-100/water mixtures are in good agreement with Asami's.…”

Section: B Mechanisms Of the Relaxationsmentioning

confidence: 99%

Dielectric spectroscopy study on ionic liquid microemulsion composed of water, TX-100, and BmimPF6

Chen

Nozaki

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

Articles you may be interested inWe report here a broadband dielectric spectroscopy study on an ionic liquid microemulsion (ILM) composed of water, Triton X-100 (TX-100), and 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF 6 ). It is found that the phase behavior of this ILM can be easily identified by its dielectric response. The dielectric behavior of the ILM in the GHz range is consistent with that of TX-100/water mixtures with comparable water-to-TX-100 weight ratio. It consists of the relaxations due to ethylene oxide (EO) unit relaxation, hydration water dynamics, and/or free water dynamics. The water content dependence of the EO unit relaxation suggests that this relaxation involves dynamics of hydration water molecules. In the IL-in-water microemulsion phase, it is found that bmimPF 6 molecules are preferentially dissolved in water when their concentration in water is lower than the solubility. An additional dielectric relaxation that is absent in the TX-100/water mixtures is observed in the frequency range of 10 7 -10 8 Hz for this ILM. This low-frequency relaxation is found closely related to the bmimPF 6 molecule and could be attributed to the hopping of its cations/anions between the anionic/cationic sites.

show abstract

“…A total of three relaxation processes can be observed, designated in descending order (from high to low temperature) as α, β, and γ according to the common convention [7]. The α relaxation is assigned to the interaction between the amorphous and crystalline phases (but in fact, might be masked by the dynamic percolation process [9] -not discussed here). The β process is situated in the temperature range 50-100°C and in almost the whole frequency range; it is assigned to the glass-rubber transition of the amorphous phase.…”

Section: Resultsmentioning

confidence: 99%

Dynamic dielectric properties and the γ transition of bromine doped polyacrylonitrile

Cohen¹,

Greenbaum²,

Feldman³

et al. 2007

Express Polym. Lett.

View full text Add to dashboard Cite

Abstract. Based on monitoring the γ process (the lowest temperature-relaxation) in polyacrylonitrile (PAN) by dynamic dielectric spectroscopy, new evidence for the formation of a charge transfer complex between bromine dopants and nitrile groups is presented. The experimental work is carried out on PAN and nitrile polymerized PAN with and without bromine doping and the effects of these factors on the γ process are measured. Nitrile polymerization results in diminishing of the γ process and in a 15% increase in its activation energy, whereas bromine doping produces splitting of the original γ process in PAN -coupled with a significant activation energy increase -and its complete disappearance in nitrile polymerized PAN. Both the splitting of the γ process and the higher activation energy reflect bromine-nitrile adduct formation.

show abstract

Dielectric relaxation in sodium bis(2-ethylhexyl)sulfosuccinate–water–decane microemulsions near the percolation temperature threshold

Cited by 104 publications

References 66 publications

Does transparent nematic phase exist in 5CB/DDAB/water microemulsions? From the viewpoint of temperature dependent dielectric spectroscopy

Does transparent nematic phase exist in 5CB/DDAB/water microemulsions? From the viewpoint of temperature dependent dielectric spectroscopy

Dielectric spectroscopy study on ionic liquid microemulsion composed of water, TX-100, and BmimPF6

Dynamic dielectric properties and the γ transition of bromine doped polyacrylonitrile

Contact Info

Product

Resources

About