FMR and TGA study of Fe O /ZnO
2
3
nanoparticles in PEN-b-PTMO
polymer
1
1
1
1
K. Wardal , J. Typek , N. Guskos , G. Zolnierkiewicz ,
2
3
3
E. Piesowicz , U. Narkiewicz , D. Sibera
1
Institute of Physics, West Pomeranian University of Technology, Al. Piastów 48, 70-311, Poland
2
Department of Polymer, West Pomeranian University of Technology, Al. Piastów 19, 70-311, Poland
3
Institute of Chemical and Environmental Engineering, West Pomeranian University of Technology,
Al. Piastów 17, 70-311, Poland
Eight samples containing g-Fe O /ZnO magnetic nanoparticles dispersed at concentrations of 0.05 and 0.1 wt.% in PEN-b-PTMO multiblock copolymer 2 3
have been prepared and investigated by using DTA/DSC and FMR methods. The FMR spectra of the obtained samples were registered at room temperature
(Fig. 1, Fig2). The FMR parameters (resonance field, linewidth, integrated intensity) were calculated (Table 1). Comparison with the previously studied similar nanocomposites allowed to draw conclusions about the magnetic interactions of Fe O /ZnO nanoparticles in PEN-b-PTMO polymer.2 3
The resonance field shifts towards smaller magnetic fields with the increase of Fe O content in nanoparticles (see 2 3
Table ). Similar trend is observed for the linewidth which increases with the increase of Fe O content. The integrated 2 3
intensity increases initially with the increase of Fe O content, but for 2 3 90%Fe O /10%ZnO sample a sharp drop 2 3
is registered. This is connected with decrease of ZnFe O content that 2 4 produces the magnetic response of our samples.
Figures 3 and 4 present DSC thermograms and TGA response of undoped PEN-b-PTMO polymer and this polymer with 0.1 wt.% content of 80%Fe O /20%ZnO. The melting temperature is slightly affected by the presence of low concentration of magnetic nanoparticles. The thermal and thermo-2 3
oxidative stability values of PEN-b-PTMO composites were examined by TGA response in air and argon. In air three distinct stages of degradation are observed while in argon only two steps are registered.
Fig.1 Spectrum of the polimer PEN-b-PTMO with nanofillers
concentration of 0.1% in different proportions of Fe O to the ZnO.2 3 concentration of 0.05% in different proportions of Fe O to the Fig. 2 Spectrum of the polimer PEN-b-PTMO with nanofillers
2 3
ZnO.
Table 1 The parameters of the spectrum of polimer with different concentrations of nanoparticles.
Fig. 3 TG traces of the polymer with nanoparticles in the air: a) for concentration 0.05%, b) for concentration
0.1%. Fig. 4 TG traces of the polymer with nanoparticles in argon : a) for concentration 0.05%, b) for concentration 0.1%.
Fig. 5 Dependence of FMR spectral parameters on concentration of Fe O2 3.
