Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (02): 486-490.doi: 10.3866/PKU.WHXB20110211

• SOFT MATTER • Previous Articles     Next Articles

Gelation of n-Butanol by a Catanionic Surfactant System

LU Ting, WANG Xiao-Dong, ZHANG Tao   

  1. Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, P. R. China
  • Received:2010-10-13 Revised:2010-11-24 Published:2011-01-25
  • Contact: WANG Xiao-Dong, ZHANG Tao E-mail:xdwang@dicp.ac.cn, taozhang@dicp.ac.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21003124) and Funds of the Chinese Academy of Sciences for Key Topics in Innovation Engineering (YYYJ0703).

Abstract:

The gelation of n-butanol was realized by a mixture of cationic and anionic surfactants (referred to as “catanionic surfactant”). In this study, we used sodium laurate/cetyltrimethylammonium bromide (SL/CTAB) as the catanionic surfactant. The rheological properties and microstructures of the n-butanol gel were studied using a rheometer and scanning electron microscopy (SEM). We found that the concentration and mole ratio of the catanionic surfactant affected the formation of the gel and n-butanol was only efficiently gelled in the presence of the catanionic surfactant at a suitable concentration and mole ratio. When we fixed the concentration of one component in the catanionic surfactant system, the gel viscosity increased with the concentration of the other component on the basis of gel formation. This gel was a non-Newtonian fluid and showed a shear-thinning property in rheological experiments. In addition, SEM results showed that the gel had a representative three-dimensional network structure, which was composed of zonal fibers with uniform thickness. Further investigation indicates that the hydrophobic effect between the hydrocarbon chains, the electrostatic attraction between the polar headgroups, and the hydrogen bond interaction between the surfactants and n-butanol play an important role in gel formation.

Key words: Catanionic surfactant, Physical gel, n-Butanol, Gelation, Hydrogen bond