Controlled microstructures of amphiphilic cationic azobenzene-montmorillonite intercalation compounds

Abstract

The intercalation of two amphiphilic cationic azobenzene derivatives into the interlayer space of montmorillonite has been conducted by the ion exchange reactions between sodium montmorillonite andp-(ω-trimethylammoniopentyloxy)-p′-(dodecyloxy)azobenzene bromide or p-(ω-trimethylammoniodecyloxy)-p′-(octyloxy)azobenzene bromide. X-Ray diffraction and elemental analysis results indicated that the dye cations were intercalated into the interlayer space of montmorillonite. The spectral properties as well as the X-ray diffraction results have revealed that the adsorbed azo dye cations form so-called J-like aggregates with mono- and bi-layers in the interlayer space of montmorillonite. The orientation of the chromophore was controlled by host–guest and guest–guest interactions. The intercalated azo dyes exhibit reversible trans–cis photoisomerization by UV and visible light irradiation.