New magnetic nanocomposites: Polyurethane/ Fe3O4-synthetic talc

New Fe3O4-synthetic talc was used as filler in the synthesis of PU/Fe3O4-synthetic talc nanocomposites obtained by physical mixture. The Fe3O4-synthetic talc-nanofillers were exfoliated/well dispersed into the polyurethane matrix even at high filler content of 10 wt.% as supported by XRD and TEM analyses. The SEM micrographs corroborated the good distribution of the fillers and evidenced an important morphology change with the increase of the filler content. These morphological changes caused by the balance between the hydrogen bonding among polymer/polymer, polymer/filler and filler/filler were also confirmed by topological changes as well as in the roughness values evaluated by AFM. The magnetic behavior of the nanocomposites was confirmed by means of Mossbauer transmission and magnetic measurements. The use of Fe3O4-synthetic talc for obtaining magnetic nanocomposites resulted in improved materials with superior crystallization temperature and thermal stability proving to be a simple way of avoiding dipolar attraction of magnetite and consequently the filler aggregation.