Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Kuwaharada, S. Articles by Hirosue, H. Search for Related Content GeoRef GeoRef Citation

SMECTITE QUASICRYSTALS IN AQUEOUS SOLUTIONS AS A FUNCTION OF CATIONIC SURFACTANT CONCENTRATION

¹ Kagoshima Prefecture Institute of Industrial Technology, 1445-1, Oda Hayato-cho, Aira-gun, Kagoshima Prefecture, 899-5105 Japan
² National Institute of Advanced Industrial Science and Technology, Shuku-machi, Tosu city, Saga Prefecture, 841-0052 Japan
³ Cooperative Research Center Kumamoto University, 2081-7 Tabaru, Mashiki-machi, Kamimashiki-gun, Kumamoto Prefecture, 861-2202, Japan

^* E-mail address of corresponding author: kharada{at}kagoshimait.go.jp

Quasicrystals of synthetic fluoromagnesian smectite (FMS) in dodecyltrimethylammonium chloride (DTAC) solutions were investigated as a function of the DTAC concentration by wet type X-ray diffraction (XRD) potential measurements, and dispersion and coagulation (DC) tests. The FMS had an electronegative potential and it was dispersed randomly in an aqueous suspension without DTAC. When the DTAC concentration was 0.002 mol/dm³, FMS tactoids started to develop a structure in which the layer thickness was 1.85 nm. At the isoelectric point, the DTAC concentration was 0.012 mol/dm³ and the FMS tactoid formed a regular stacked structure with a 2.25 nm layer thickness. As the potential of FMS changed from negative to positive, the DC test and XRD measurement showed that the FMS association gradually changed from coagulation to dispersion, which indicates that the formation of the bilayer of surfactants on the surface of FMS produces a repulsion between DTA⁺ adsorbed on the silicate layer of the FMS surfaces. When the equilibrium concentration of DTAC in solution exceeded the critical micelle concentration (CMC), the potential of FMS became greater than the previous values. The XRD analysis of this suspension showed that there were two kinds of rational FMS stackings; one has a layer thickness of 3.20 nm, and the other has a layer thickness of 5.45 nm due to an interstratified structure composed of 3.20 and 2.25 nm layers. The interstratified structure was confirmed by the calculated XRD profiles.

Key Words: Calculated XRD Profile • Interstratification • Layer Thickness • Quasicrystal • Stacking Structure • Wet Type XRD • Potential

This article has been cited by other articles:

				B. Schampera and S. Dultz Determination of diffusive transport in HDPy-montmorillonite by H2O-D2O exchange using in situ ATR-FTIR spectroscopy Clay Minerals, June 1, 2009; 44(2): 249 - 266. [Abstract] [Full Text] [PDF]

				Y. Imai, Y. Imai, S. Nishimura, Y. Inukai, and H. Tateyama DIFFERENCES IN QUASICRYSTALS OF SMECTITE-CATIONIC SURFACTANT COMPLEXES DUE TO HEAD GROUP STRUCTURE Clays and Clay Minerals, April 1, 2003; 51(2): 162 - 167. [Abstract] [Full Text] [PDF]