Airbrushed Polysulfone (PSF)/Hydroxyapatite (HA) Nanocomposites: Effect of the Presence of Nanoparticles on Mechanical Behavior Articles uri icon

publication date

  • February 2022

start page

  • 753

end page

  • 773

issue

  • 4

volume

  • 14

International Standard Serial Number (ISSN)

  • 2073-4360

abstract

  • Nanocomposite films of polysulfone (PSF)—hydroxyapatite (HA) were prepared with a
    commercial airbrush. Structural, thermal, and mechanical characterization allows obtaining new information
    to understand the role of the nanofiller–polymer matrix interphase in the final performance
    of these materials in relation to its possible applications in the restoration of bones. Fourier-transform
    infrared spectroscopy shows that there are hardly any structural changes in the polymer when adding
    HA particles. From thermal analysis (differential scanning calorimetry and thermogravimetry), it can
    be highlighted that the presence of HA does not significantly affect the glass transition temperature
    of the PSF but decelerates its thermal degradation. All this information points out that any change in
    the PSF performance because of the addition of HA particles cannot be due to specific interactions
    between the filler and the polymer. Results obtained from uniaxial tensile tests indicate that the addition
    of small amounts of HA particles (1% wt) leads to elastic moduli higher than the upper bound
    predicted by the rule of mixtures suggesting there must be a high contribution of the interphase. A
    simple model of the nanocomposite is proposed for which three contributions must be considered,
    particles, interphase and matrix, in such a way that interphases arising from different particles can
    interact by combining with each other thus leading to a decrease in its global contribution when
    the amount of particles is high enough. The mechanical behavior can be explained considering a
    balance between the contribution of the interphase and the number of particles. Finally, a particular
    mechanism is proposed to explain why in certain nanocomposites relatively high concentrations of
    nanoparticles may substantially increase the strain to failure.

keywords

  • polysulfone; hydroxyapatite; nanocomposites; interphases; mechanical properties