HIGH DISPERSION BARIUM SULFATE NANOPARTICLES PREPARED WITH DODECYL BENZENE SULFONIC ACID

摘要

Production of nanoparticles by precipitation is a relatively simple process but the control of product particle size distribution is difficult. In this paper, nanosize barium sulfate (BaSO_4) particles are prepared with dodecyl benzene sulfonic acid (DBSA) in ethanol_water reaction system at room temperature. The BaSO_4 nanoparticles are characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), powder X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA), respectively. The results indicated that the average diameter of spherical BaSO_4 is about 46 nm modified with 5 wt.% DBSA, which have good dispersion in the presence of a certain concentration NH_3·H_2O. It suggests that the high dispersion is attributed to presence of a thin layer of barium alkyl sulfate, which is formed and coated onto the surface of BaSO_4 particles during the reaction process. The thin films on the surface of the BaSO_4 effectively modified the surface and properties, which also control the particle size and morphology.