Synthesis and characterization of UV curable polyurethane-acrylate nanocomposite-based coatings enhanced with magnesium fluoride nanoparticles.

AbstractThis study contributes valuable insights into optimizing ultraviolet-curable synthesized polyurethane-acrylate (PUA) coatings through tailored MgF2 nanocomposite formulations. The chemical structure of PUA was analyzed via Fourier transform infrared spectroscopy, confirming strong interactions between MgF2 nanoparticles and PUA segments. The interactions were further supported by thermogravimetric analysis and dynamic mechanical thermal analysis, highlighting enhanced thermal stability and viscoelastic properties in the nanocomposites compared to neat PUA coating. Thermogravimetry exhibited a notable increase in temperature of maximum degradation rate with higher MgF2 content, from 420.9 °C for neat PUA to 436.5 °C for PUA nanocomposites, indicating improved thermal stability with MgF2 integration. Analysis of viscoelastic behavior of the coatings revealed that storage modulus of the nanocomposites are higher than that of neat PUA, which is an indication of reinforcing effect of MgF2 nanoparticles. The damping factor curves demonstrated broadening and significant positive shifts (more than 33 °C) in glass transition temperature for the nanocomposites compared to neat PUA, providing additional evidence of strong interactions between MgF2 and PUA. Morphology and nanoparticle dispersion in the nanocomposites were also investigated. Contact angle measurements indicated improved wettability with increasing MgF2 content, reaching 44.4° for the nanocomposite containing 5 wt.% MgF2. [ABSTRACT FROM AUTHOR]