Synthesis and characterization of poly(vinyl phosphonic acid) (PVPA)–Fe3O4 nanocomposite

• Published in: Polyhedron Vol. 30; no. 2; pp. 419 - 426
• Main Authors: Durmus, Z., Erdemi, H., Aslan, A., Toprak, M.S., Sozeri, H., Baykal, A.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2011
• Subjects: Chemistry; Conducting polymer; Electrical properties; Kemi; Magnetite; Magnetization; Nanocomposite; NATURAL SCIENCES; NATURVETENSKAP; Nanocomposite; Magnetite; Electrical properties; Conducting polymer; Magnetization
• ISSN: 0277-5387; 1873-3719
• DOI: 10.1016/j.poly.2010.11.011

Poly(vinyl phosphonic acid) (PVPA)–Fe3O4 nanocomposite is synthesized by the precipitation of Fe3O4 in the presence of PVPA. Structural, surface, morphological, thermal properties and conductivity characterization/evaluation of the nanocomposite were performed by XRD, FT-IR, TEM, TGA and conductivity measurements, respectively. The capping of PVPA around the Fe3O4 nanoparticles was confirmed by FT-IR spectroscopy, the interaction being via bridging oxygens of the phosphate and the nanoparticle surface. The crystallite and particle size were obtained as 6±2 and 8.7±0.1nm from XRD line profile fitting and TEM image analysis respectively, which reveal nearly single crystalline nature of the Fe3O4 nanoparticles. Magnetic characterization of the bulk magnetite and (PVPA)–Fe3O4 nanocomposite reveals that both are in the superparamagnetic state at room temperature. The average magnetic domain size of the nanoparticles has been calculated using the Langevin function, which was fitted to the measured M–H hysteresis curves as 7.6nm for the nanocomposite. In the nanocomposite, the reduction is due to the adsorption of PVPA onto the magnetite surface, which cancels some of the free spins at the surface causing a magnetically dead layer. Analysis of the conductivity and permittivity measurements revealed the coupling of ionic and polymer segmental motions and strong temperature dependency in the nanocomposite. [Display omitted] ► PVPA coated Fe3O4 nanoparticles have been prepared by the in situ polymerization of PVPA for the first time. ► As a nanocomposite, its dielectric, magnetic, structural and morphological properties were investigated in detail for the first time. ► Organic/inorganic nanocomposite membranes consisting of Fe3O4/PVPA (polyvinyphosphonic acid) hybrids showed a maximum ionic conductivity of 1.0×10−7S/cm at 120°C. ► Although this low conductivity precludes its use, it still has wide technological applications, particularly in biotechnology. Poly(vinyl phosphonic acid) (PVPA)–Fe3O4 nanocomposite is synthesized by the precipitation of Fe3O4 in the presence of PVPA. Structural, surface, morphological, thermal properties and conductivity characterization/evaluation of the nanocomposite were performed by XRD, FT-IR, TEM, TGA and conductivity measurements respectively. The capping of PVPA around the Fe3O4 nanoparticles was confirmed by FT-IR spectroscopy, the interaction being via bridging oxygens of the phosphate and the nanoparticle surface. The crystallite and particle size were obtained as 6±2 and 8.7±0.1nm from XRD line profile fitting and TEM image analysis respectively, which reveal nearly single crystalline nature of the Fe3O4 nanoparticles. Magnetic characterization of the bulk magnetite and (PVPA)–Fe3O4 nanocomposite reveals that both are in the superparamagnetic state at room temperature. The average magnetic domain size of the nanoparticles has been calculated using the Langevin function, which was fitted to the measured M–H hysteresis curves as 7.6nm for the nanocomposite. In the nanocomposite, the reduction is due to the adsorption of PVPA onto the magnetite surface, which cancels some of the free spins at the surface causing a magnetically dead layer. Analysis of the conductivity and permittivity measurements revealed the coupling of ionic and polymer segmental motions and strong temperature dependency in the nanocomposite.