Intercalation of a Nonionic Surfactant (C10E3) bilayer into a Na-Montmorillonite Clay

TL;DR

This study demonstrates the intercalation of a nonionic surfactant, C10E3, into Na-montmorillonite clay, forming a bilayer that expands the interlayer space and preserves clay properties, opening new avenues for hybrid nanomaterials.

Contribution

It reveals the formation of a bilayer of nonionic surfactant within clay interlayers, differing from previous monolayer confinement, enabling new functional hybrid materials.

Findings

A bilayer of C10E3 was successfully intercalated into Na-montmorillonite.

The intercalation preserves clay's electrostatic properties and allows further ion exchange.

The interlayer space expansion exceeds previous monolayer limits.

Abstract

A nonionic surfactant, the tri-ethylene glycol mono n-decyl ether (C10E3), characterized by its lamellar phase state, was introduced in the interlayer of a Na-montmorillonite clay at several concentrations. The synthesized organoclays were characterized by Small Angle X-Ray Scattering in conjunction with Fourier Transform Infrared spectroscopy, and adsorption isotherms. Experiments showed that a bilayer of C10E3 was intercalated into the interlayer space of the naturally exchanged Na-montmorillonite, resulting in the aggregation of the lyotropic liquid crystal state in the lamellar phase. This behavior strongly differs from previous observations of confinement of nonionic surfactants in clays where the expansion of the interlayer space was limited to two monolayers parallel to the silicate surface and cationic surfactants in clays where the intercalation of organic compounds is introduced into the clay galleries through ion exchange. The confinement of a bilayer of C10E3 nonionic surfactant in clays offers new perspectives for the realization of hybrid nanomaterials since the synthesized organoclays preserve the electrostatic characteristics of the clays, thus allowing further ion exchange, while presenting at the same time a hydrophobic surface and a maximum opening of the interlayer space for the adsorption of neutral organic molecules of important size with functional properties.