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Coating of ZnO nanoparticles by polyethylene glycol

Polymer coating is an effective way for modifying he particle surface. Polymer adsorption by nanoparticles improves the stability of the suspension against aggregation. In order to prevent nanoparticles from aggregation، in this work، zinc oxide nanoparticles and polyethylene glycol (PEG) are used as nano-sized metal oxide powder and adsorbed polymer، respectively. The adsorption process is analyzed by the infrared spectroscopy (IR) technique. The size and structure of zinc oxide nanoparticles have been characterized by X-ray diffraction (XRD). The amount of the adsorbed polymer was measured by thermogravimetry analysis (TGA) method. Moreover، the aggregation and accumulation of the nanoparticles was studied using scanning electron microscopy (SEM). We found that، using the polymers with lower average molecular weight made nanoparticles with higher adsorption، lower size، and a more spherical shape. Our results show that the coating process is an effective way of avoiding aggregation، sticking، and clumping of nanoparticles.