Heterogeneous distribution of magnetic nanoparticles in reactive polymer blends

Magnetic Self-Healing Composites: Synthesis and Applications

Magnetic composites and self-healing materials have been drawing much attention in their respective fields of application. Magnetic fillers enable changes in the material properties of objects, in the shapes and structures of objects, and ultimately in the motion and actuation of objects in response to the application of an external field. Self-healing materials possess the ability to repair incurred damage and consequently recover the functional properties during healing. The combination of these two unique features results in important advances in both fields. First, the self-healing ability enables the recovery of the magnetic properties of magnetic composites and structures to extend their service lifetimes in applications such as robotics and biomedicine. Second, magnetic (nano)particles offer many opportunities to improve the healing performance of the resulting self-healing magnetic composites. Magnetic fillers are used for the remote activation of thermal healing through inductive heating and for the closure of large damage by applying an alternating or constant external magnetic field, respectively. Furthermore, hard magnetic particles can be used to permanently magnetize self-healing composites to autonomously re-join severed parts. This paper reviews the synthesis, processing and manufacturing of magnetic self-healing composites for applications in health, robotic actuation, flexible electronics, and many more.

Effect of carbon nanotubes on morphology evolution of polypropylene/polystyrene blends: understanding molecular interactions and carbon nanotube migration mechanisms

MWCNT migration among domains in conjunction with viscosity and elastic effects are important factors governing the morphological changes in the PP:PS blend nanocomposites.

Improved thermal conductivity and flame retardancy in polystyrene/poly(vinylidene fluoride) blends by controlling selective localization and surface modification of SiC nanoparticles

The effect of selective localization of silicon carbide (SiC) and polystyrene (PS)-coated SiC (p-SiC) nanoparticles on the thermal conductivity and flame retardancy of immiscible PS/poly(vinylidene fluoride) (PVDF) blends has been systematically studied. The scanning electron microscopy (SEM) images reveal that SiC and p-SiC nanoparticles have different selective localizations in the PS/PVDF blends. The melting and crystallization behaviors of the PVDF component investigated by using differential scanning calorimetry are consistent with the SEM results. To reduce the volume fraction of fillers in the composites, a cocontinuous structure of PS/PVDF has also been built up. The cocontinuity window for PS/PVDF blends is ∼30-70 vol % according to the selective solvent dissolution technique. The selective localization of SiC in the PVDF phase of the PS/PVDF 70/30 blends produces a slightly higher thermal conductivity than that of p-SiC in the PS phase of the PS/PVDF 30/70 blends. However, the composites with selective localization of p-SiC exhibit the best combined properties of thermal conductivity and flame retardancy.