DOI: https://doi.org/10.55373/mjchem.v28i1.434

Keywords: Polymethyl methacrylate (PMMA), zirconium oxide nanoparticles (ZrO₂), hardness, impact strength, iron oxide nanoparticles (Fe₂O₃), nanocomposite

Abstract

Polymethyl methacrylate (PMMA) is extensively employed as a denture base material owing to its biocompatibility, antimicrobial qualities, and advantageous physical characteristics. However, its natural brittleness and limited mechanical strength make it less effective in the clinic. This study aims to enhance the mechanical properties of PMMA by incorporating zirconium oxide (ZrO₂) and iron oxide (Fe₂O₃) nanoparticles at different concentrations (1 wt%, 2 wt%, and 3 wt%) using hydrothermal autoclave. Two groups of nanocomposites were produced and underwent post-curing heat treatment to examine the impact of nanoparticle type and concentration on the mechanical properties of the material. Mechanical studies indicated that PMMA reinforced with nano-ZrO₂/Fe₂O₃ displayed lower impact resistance, especially post-heat treatment, in contrast to PMMA reinforced purely with ZrO₂ nanoparticles. The inclusion of Fe₂O₃ appears to decrease toughness instead of boosting it. Of the studied formulations, heat-treated PMMA with 3 wt% nano-ZrO₂ displayed the most advantageous balance of strength and durability, indicating excellent nanoparticle distribution and interfacial adhesion. The findings underscore the potential of regulated nano-ZrO₂ integration to enhance the mechanical dependability of denture base materials, but hybrid reinforcement with Fe₂O₃ offers no supplementary advantages under the assessed conditions.