Magnetic studies of polystyrene/iron-filled multi-wall carbon nanotube composite films

Abstract

Polystyrene / iron-filled multi-wall carbon nanotube composite films were prepared by solution processing, forge-rolling and stretching methods. Elongated iron carbide nanoparticles formed because of catalytic growth are situated inside the hollow cavity of the nanotubes. Magnetic susceptibility measurements as well as records of isothermal hysteresis loops performed in three perpendicular directions of magnetic field confirmed that the nanotubes have a preferential alignment in the matrix. Strong diamagnetic anisotropy in the composites emerges not only from the MWCNTs but also from the polystyrene matrix. The polymer sticks to the honeycomb lattice through the interaction of the S-orbitals of the phenyl ring and those of the carbon nanotube, contributing to anisotropic diamagnetic response. The contribution of iron nanoparticles to overall magnetic response strongly depends on nanotube concentration in the composite as well as on matrix-filler non-covalent stacking, which influences magnetic interparticle interactions.

Synergistic effect of carbon nanofiber decorated with iron oxide in enhancing properties of styrene butadiene rubber nanocomposites

“…This result was mainly attributed to the effect of CNF on the proportion of Fe 2 O 3 nanomaterials in the elastomer composites. The saturation magnetization of the CNF‐Fe 2 O 3 elastomer composites depends on the mass fraction of the Fe 2 O 3 nanoparticles rather than the dispersion and interaction of the CNF‐Fe 2 O 3 in the elastomer matrix …”

Electrospinning of polymer nanofibers containing carbon nanotubes filled with iron nanowires

“…In this study, we attempted to form CNT/polymer composite nanofibers using CNTs filled with iron (Fe) nanowires (hereafter, called "Fe@CNTs"). Fe@CNTs [18][19][20][21][22][23][24][25][26][27][28][29][30][31] are CNTs that encapsulate Fe nanowires in the inner hollows. The Fe nanowires have high-aspect-ratio shapes (typically 40 nm in diameter and 10 μm in length).…”

“…Electrospinning may possibly form ferromagnetic polymer nanofiber sheets with a controlled magnetization direction by aligning the polymer fiber direction in the sheets, which is impossible using conventional Fe@CNT/ polymer composites. 24,32) Fe@CNTs/polymer sheets have various applications, such as magnetic shield, flexible permanent magnet, flexible electronic devices, etc.…”

Iron-filled multi-walled carbon nanotubes for terahertz applications: effects of interfacial polarization, screening and anisotropy

“…Сarbon nanotubes (CNTs) possessing excellent conductivity are of great interest for the electromagnetic shielding applications. Addition of even a small amount of CNTs into a polymer matrix leads to the significant enhancement of electromagnetic absorbing performance of the material [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Electromagnetic response of the composites containing CNTs can be tuned by changing the nanotube length, diameter [16,[19][20][21][22], and number of layers [19,27,28] as well as the CNT dispersion [12,18,25] and arrangement [14,16,18,[24][25][26] in the matrix.…”