Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
597532 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2007 | 7 Pages |
Abstract
Colloidal dispersions of Mg-Al (Mg/Al molar ratio 2:1) layered double hydroxide (LDH) have previously been found to exhibit an isotropic-nematic (I-N) phase transition [S.Y. Liu, J. Zhang, N. Wang, W.R. Liu, C.G. Zhang, D.J. Sun, Chem. Mater. 15 (2003) 3240-3241]. In the present paper, we show that an effective attraction induced by the addition of low molecular weight polyethylene glycol (PEG) enriches the phase behavior of Mg-Al LDH dispersions. At certain concentrations of LDH and PEG, multiphase coexistence is observed. The addition of PEG leads to the appearance of a four-phase equilibrium and even a five-phase equilibrium. We explain the experimental phenomena by the interplay between PEG-induced effective attraction, LDH particle polydispersity and sedimentation.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Colloid and Surface Chemistry
Authors
Wenxia Zhu, Dejun Sun, Shangying Liu, Ning Wang, Jie Zhang, Lingyu Luan,