Synthesis and characterization of poly(acrylonitrile-co-methylmethacrylate) nanocomposites reinforced by functionalized multiwalled carbon nanotubes

Polyacrylonitrile-co-poly(methylmethacrylate)/multiwalled carbon nanotubes (PAN-co-PMMA/MWCNTs) nanocomposites were synthesized by an in situ emulsifier-free polymerization method with variable percentages of functionalized carbon nanotube (f-MWCNT). MWCNTs were functionalized with concentrated H2SO4 and HNO3 with a continuous sonication process. Chemical interaction of f-MWCNT with the copolymer was studied by UV-visible spectroscopy. Fourier transform infrared spectroscopy proved the interaction of f-MWCNT with the PAN-co-PMMA copolymer matrix. The structural interaction of f-MWCNT with copolymer matrix was investigated by X-ray diffraction study. The dispersion and morphology of the f-MWCNT in the copolymer matrix were studied by scanning electron microscopy and high-resolution transmission electron microscopy. It was noticed that the f-MWCNTs were uniformly dispersed within the copolymer matrix. The thermal property of the PAN-co-PMMA/f-MWCNT nanocomposite was analyzed by thermogravimetric analysis. It was noticed that the thermal stability of the PAN-co-PMMA/f-MWCNT nanocomposite was more than that of the virgin copolymer matrix. When the electrical conductivity property of the synthesized nanocomposite was measured, it was noticed that the better dispersion of f-MWCNT in the non-conductive PAN-co-PMMA copolymer matrix made the PAN-co-PMMA/f-MWCNT nanocomposites conductive. From the measurement of gas barrier properties of synthesized nanocomposites, it was assumed that the well-dispersed f-MWCNT in the copolymer matrix creates the huddles for penetration of oxygen gas. It was noticed that the oxygen permeability of the PAN-co-PMMA/f-MWCNT nanocomposite was reduced by five times as compared to that of the neat PAN-co-PMMA copolymer matrix. The PAN-co-PMMA/f-MWCNT nanocomposites with higher thermal stability and reduced oxygen permeability properties may be suitable for application as conducting packaging materials.