Fabrication and characterization of poly methyl methacrylate (PMMA) matrix modified with strontium nano-rods

TL;DR

This study explores how adding strontium oxide nanorods to PMMA affects its properties, showing improved thermal stability and hardness but reduced toughness.

Contribution

The novelty lies in the fabrication and characterization of PMMA composites modified with strontium nanorods, revealing their structural and antibacterial performance.

Findings

PMMA composites with SrO nanorods showed increased hardness and Young’s modulus but reduced elongation-at-break.

Thermogravimetric analysis showed enhanced thermal stability with higher onset temperatures and reduced mass loss.

Antibacterial tests demonstrated effectiveness against E. coli, S. aureus, and C. albicans.

Abstract

In this study, strontium oxide nanorods (SrO NRs) were synthesized and incorporated into PMMA matrices at 1–5 wt% to evaluate structural, thermal, mechanical, surface, and antibacterial performance. XRD combined with FTIR confirmed the presence of residual Sr-based hydroxide and carbonate phases associated with SrO synthesis routes, contributing to composite interfacial interactions. Tensile tests revealed no statistically significant enhancement in tensile strength, despite increases in hardness and Young’s modulus, which is consistent with a shift toward higher stiffness rather than enhanced toughness. Increased stiffness was accompanied by reduced elongation-at-break, indicating SrO-induced embrittlement, especially at high loading. Surface roughness increased progressively with SrO content, correlating with the successful incorporation of nanorod fillers into the PMMA matrix, as evidenced by SEM/EDX analysis. Thermogravimetric analysis elevated thermal stability for nanofiller-loaded PMMA, with higher onset temperatures and reduced mass loss relative to neat PMMA. It may be inferred that the degradation process is influenced by the thermal dihydroxylation and decarbonation of the nanofiller itself, rather than solely by polymer degradation mechanisms, which delays the overall mass-loss kinetics. Antibacterial assays against gram-negative bacteria (E. coli), gram-positive bacteria (S. aureus), and the fungus (C. albicans) were evaluated. The combined improvements in thermal stability, density, and hardness indicate that the reinforced PMMA represents a promising material for certain functional properties except for applications requiring high toughness.

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