Surface modification of natural fibrous brucite with stearic acid

Abstract

Fibrous brucite, a kind of brucite with unique structure and physical properties, was modified with stearic acid as a surface modifier. In order to investigate the mechanism of surface modification, the fixation of stearic acid on fibrous brucite and the induced changes in surface properties were studied by using X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR), Raman spectroscopy and thermo-gravimetric analysis (TGA). XRD analysis indicates that the modification of fibrous brucite with stearic acid does not cause any changes in the structure of fibrous brucite mineral. Spectroscopy and thermal analysis show that the surfactant molecules are not only directly adsorbed on the surface of the mineral, but also chemisorbed on mineral surface by forming chemical bonds between the modifier and magnesium hydroxide.

Keywords

fibrous brucite / modification / stearic acid / surface properties

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