Synthesis, physical and magnetic properties of BaFe12O19/P(VDF-TrFE) multifunctional composites.

Composite films with filler microparticles of Barium ferrite BaFe 12 O 19 (BaFO, 1–20 wt.%) dispersed within P(VDF-TrFE) acting as piezoelectric polymeric matrix have been prepared by solvent evaporation. SEM and TEM images in combination with magnetic measurements clearly probe the good dispersion and random distribution of the BaFO microparticles within the films. Young’s modulus of the fabricated composites remains almost unchanged for all filler contents, indicating that this acts as a small defect within the P(VDF-TrFE) matrix. On the contrary, dielectric properties clearly reduce for low filler contents, 1 and 5 wt.%, and recover and increase their values in a smooth and monotonous way for higher BaFO filler contents of 10 and 20 wt.%. This trend is not followed by the electrical conductivity. Additionally, we have extended the study to fibers composed of BaFe 12 O 19 microparticles within a PVDF matrix. Due to the big size of BaFO particles (about 1 μm in diameter), a proper fabrication of the fiber shaped composites has not been achieved. We found that true BaFO content are always lower than nominal ones. Results are discussed in terms of the influence of size and morphology of the BaFO particles on the initial properties of the pure polymeric matrix. [ABSTRACT FROM AUTHOR]