Enhanced Multifunctional Properties of Poly(Methyl Methacrylate)/Nickel Oxide Nanocomposites for Flexible Electronic and Dielectric Applications

ABSTRACT

In the present study, polymethyl methacrylate (PMMA)/nickel oxide (NiO) nanocomposites were successfully synthesized via in situ free radical polymerization, and their structural, morphological, optical, thermal, mechanical, electrical, and dielectric properties were systematically examined to assess the influence of improved interfacial compatibility and uniform nanoparticle dispersion. FTIR confirmed the characteristic PMMA functional groups and interactions between PMMA chains and NiO nanoparticles, suggesting the formation of PMMA/NiO nanocomposites. UV–Vis spectroscopy revealed the lowest optical bandgap energy and maximum refractive index at 7 wt% NiO loading. FE‐SEM and HR‐TEM showed uniform dispersion and nanoscale homogeneity of NiO within the polymer matrix. Contact angle measurements indicated enhanced hydrophobicity upon nanoparticle addition. TGA revealed improved thermal stability, as evidenced by a shift in degradation temperature to higher values. The nanocomposite showed higher tensile strength and Young's modulus, along with reduced elongation at break. The integration of NiO nanoparticles into PMMA increased the conductivity with increasing filler content and temperature, with the 7 wt% composite exhibiting optimal conductivity. The PMMA/7 wt% composite showed the lowest activation energy, while the dielectric constant increased by nearly five times. Overall, the 7 wt% NiO nanocomposite exhibited superior multifunctional performance, highlighting its potential for advanced polymer‐based applications.