Process For Obtaining Functionalized Nanoparticulate Magnetic Ferrites for Easy Dispersion and Magnetic Ferrites Obtained Through the Same

摘要

The present invention refer to a innovative process for obtaining nanoparticulate magnetic ferrites, at low temperatures, simple or mixed, functionalized by organic molecules, for dispersion of these nanoparticles in polar or nonpolar media, and the same particles dispersed in a liquid medium, also known as ferrofluids. The present invention enables obtaining both simple ferrites (MFe₂O₄ or MFe₁₂O₁₉) and mixed ferrites (N_x M_(1−x)Fe₂O₄ or N_1−Y M_x+Y Fe_(2−x)O₄; as example) where M and N can be metals, such as Sm, La, Bi, Ba, Mo, Sr, Ni, Fe, Mn, Cr, etc., through the coprecipitation method, functionalized by organic molecules containing carboxylic groups, which are polymers, or long chain acids or short chain acids, containing mono, di or tricarboxylic groups and/or alcohols, whose dispersion in polar or nonpolar media is improved. The present invention enables also obtaining ferrofluids, through the mixture of the obtained magnetic particles with an appropriate liquid carrier. The substitution of some elements in the ferrites may yield specific mechanical, optical and/or magnetic properties.