Magnetic magnetite/epoxy nanocomposites with polyaniline as coupling agent: preparation, characterization, and property

An in situ polymerization method fabricated the electrically conductive magnetic epoxy nanocomposites with magnetite@polyaniline. With the introduction of polyaniline on the magnetite nanoparticles, the structural integrity of the synthesized epoxy nanocomposites was enhanced with the bridging effect of the polyaniline. Specifically, compared with pure epoxy, the tensile strength was improved to 82.2 MPa when 1.0 wt% magnetite@polyaniline was added to the epoxy matrix. The enhanced mechanical property is due to the enhanced interfacial interaction. With further increasing particle loading to 30.0 wt%, glass transition temperature (T_g) was decreased to 85.4 °C, which is related to the enlarged free volume between epoxy chains. The saturation magnetization of 30.0 wt% magnetite@polyaniline/epoxy composites was 12.79 emu/g. Moreover, with the assistance of magnetite@polyaniline, the thermal stability was enhanced compared with pure epoxy. The electromagnetic wave absorption of the unique magnetite@polyaniline/epoxy nanocomposites was also studied. When the content of magnetite@polyaniline reached 30.0 wt%, the reflection loss even reached − 35.9 dB. This work guides the fabrication of multifunctional epoxy nanocomposites with comprehensive electrical, magnetic, and mechanical properties.

Magnetite epoxy nanocomposites with polyaniline as coupling agent with enhanced electromagnetic wave absorption performance