Surface and interface physicochemical aspects of intercalated organo-bentonite

The detailed understanding of the surface and interface physicochemical aspects of intercalated organo-bentonite is of importance in the design of organoclay based materials and in their industrial applications. In this study X-ray photoelectron spectroscopy (XPS), diffuse reflectance infrared Fourier transform spectra (DRIFT), X-ray diffraction (XRD) have been used to provide new insights into the surface composition, surface functional groups, interlayer structure and morphology of hexadecyl trimethyl ammonium bromide (HDTMAB)/bentonite organoclays (oMMT). Inverse gas chromatography (IGC) is used for understanding the effect of the HDTMAB on the dispersive component of the surface energy ( γ S d ) which is closely related with the adhesion and wettability properties of materials. The increasing amount of HDTMAB in organoclays was found to significantly reduce the γ S d values up to 1.5 oMMT. 1.5 oMMT and 2 oMMT values were found so closer to each other. More importantly, the γ S d values were correlated with the XPS-determined surface N/Al atomic ratio, taken as a chemical descriptor for the modification of the clay.