Intercalation of cetyl trimethylammonium ion into sericite in the solvent of dimethyl sulfoxide

In order to improve the microenvironment between layers of sericite in the manufacture of polymer/sericite nanocomposites, a pre-modified sericite was intercalated by cetyl trimethylammonium ion (CTA+) in a dimetzhyl sulfoxide (DMSO) solvent. The relevant experimental conditions, such as intercalating time, temperature, solid content and pH value, were optimized, and the intercalated sericite was characterized by X-ray diffraction, Fourier transform infrared, and X-ray photoelectron spectroscopy analyses. At an intercalation rate of 94%, the amount of CTA+ intercalated in the interlayer space of sericite was 36.3% and an expansion of d001 value from 1.00 nm to 5.07 nm was observed. The intercalated CTA+ in the interlayer space of sericite adopted a paraffin-type bilayer configuration with a tilting angle of 53.6°. Due to its unique structure, DMSO would be better than water as the solvent for intercalation of organic cations. The intercalated sericite was more suitable to combine with polymer to form polymer/sericite nanocomposites.

► DMSO was used as solvent for intercalation of sericite.
► A three step pre-treatment was performed before interaction.
► The intercalation resulted in d001 expansion of sericite from 1.00 nm to 5.07 nm.
► The intercalated organic cation adopted a paraffin-type bilayer configuration.