Insights into the optical, magnetic and dielectric properties of some novel polysulfone/NiFe₂O₄ composite materials

Abstract

Novel polysulfone (PSU)/NiFe 2 O 4 nanocomposites with good magneto-dielectric properties were prepared in a simple and cost-effective manner. Nickel ferrite nanoparticles exhibit a cubic spinel phase without any impurity phases according to X-ray diffraction characterization. Transmission electron microscopy images of the nanoparticles showed a tetragonal particle shape with average particle size of 17-30 nm. The thermal stability of PSU proved to remain unaffected by nanoparticle concentration in the composite material. The emission spectra of the PSU/NiFe 2 O 4 nanocomposites present a broad emission band located at 370 nm due to free exciton recombination. The composites exhibit hysteresis loops of a ferrimagnetic nature and good dielectric properties. Coercivity value measured at room temperature is 20.64 and 24.98 Oe and the squareness (M r /M s ) is 0.290 and 0.225 for both polymer composite samples (4 and 24 vol% Ni ferrite). The formalism of the dielectric loss has been used to estimate the dipolar relaxations expressed by -and -relaxation processes. The presence of Ni ferrite nanoparticles in the PSU matrix increases the activation energy of secondary relaxations, which means a reduction of the molecular mobility in the nanocomposites as compared to PSU.

Novel low‐dielectric‐constant fluorine‐functionalized polysulfone with outstanding comprehensive properties

“…As a kind of special engineering plastic, PSU has been considered as a potential candidate for the next generation of high‐performance polymer dielectrics, due to its outstanding comprehensive properties . The aromatic constituent in PSU can endow the polymer with outstanding mechanical and thermal properties, and the aryl ether (–O–) benefits the polymer processing while keeping good dimensional stability.…”

Magneto-Dielectric Behaviour of M-Type Hexaferrite/Polymer Nanocomposites

“…Ferrites in their single crystal or ceramic form have been studied as monolithic materials [9,24,25]. In contrast, scarce attention has been given to ferrite/polymer nanocomposites [14,26] although ferrite nanoparticles could be beneficial to a bunch of composite properties including mechanical, electrical and magnetic performance. The quality of the developed systems was investigated via scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectra, while dielectric and magnetic response were studied by means of broadband dielectric spectroscopy (BDS) and magnetization measurements employing a SQUID magnetometer, respectively.…”

Synthesis, characterization, electrical, and magnetic properties of polyvinyl alcohol/carboxymethyl cellulose blend doped with nickel ferrites nanoparticles for magneto‐electronic devices

“…54-0964). 31 By applying the following Debye-Scherrer formula, the particle mean size (Dhkl) was determined 32 :…”