In this review, recent progress in the mechanical, thermal and interfacial properties of graphene/CNT multiphase polymer composites is examined. Progress in the mechanical and thermal properties of CNT (1D) and graphene (2D) nanostructure materials is also reviewed and compared. Furthermore, this review highlights the improvements in the mechanical, thermal and interfacial properties of two- and three-phase composites, owing to the addition of graphene/CNT. In particular, analysis of several notable papers on hybrid composites (graphene/CNT) provides an intensive review of synergetic effects on the overall properties of the corresponding composites. This holistic review describes an improved interface between fibers and a nanofiller-reinforced matrix. Although the presence of nanofillers even at low loadings confers an overall improvement in composite properties, the exact ratios of individual fillers and combined forms remain to be discussed in depth. Finally, potential applications, current challenges and future perspectives for use of these multiphase composites are discussed with regard to their extraordinary capabilities and promising developments in graphene/CNT family-based composite materials.

Carbon nanotube- and graphene-reinforced multiphase polymeric composites: review on their properties and applications

We report the preparation of epoxy-based composites with enhanced dielectric properties and thermal conductivity, by employing intelligently designed core/shell Alumina/Polydopamine (indicated as AO*) and strawberry-like core/shell structured Alumina/Polydopamine/Silver (indicated as AO*@Ag) particles as fillers. The introduction of the core-shell AO* and AO*@Ag particles into the epoxy matrix can distinctly enhance both the dielectric permittivity and dielectric breakdown strength of composites, as compared to that incorporating AO particles as fillers. For example, the dielectric breakdown strength of AO*@Ag/epoxy with 22.9 vol% filler loading is up to 65.5 kV/mm, representing an improvement of 24% compared with AO/epoxy composite at the same filler loading (52.8 kV/mm), while it has enhanced dielectric permittivity at room temperature at low frequency. Additionally, the strawberry-like core/shell particle-filled composites still take on a high thermal conductivity.

Dielectric properties and thermal conductivity of epoxy composites using quantum-sized silver decorated core/shell structured alumina/polydopamine

A novel class of carbon nanotube (CNT)-based nanomaterials has been surging since 1991 due to their noticeable mechanical and electrical properties, as well as their good electron transport properties. This is evidence that the development of CNT-reinforced polymer composites could contribute in expanding many areas of use, from energy-related devices to structural components. As a promising material with a wide range of applications, their poor solubility in aqueous and organic solvents has hindered the utilizations of CNTs. The current state of research in CNTs—both single-wall carbon nanotubes (SWCNT) and multiwalled carbon nanotube (MWCNT)-reinforced polymer composites—was reviewed in the context of the presently employed covalent and non-covalent functionalization. As such, this overview intends to provide a critical assessment of a surging class of composite materials and unveil the successful development associated with CNT-incorporated polymer composites. The mechanisms related to the mechanical, thermal, and electrical performance of CNT-reinforced polymer composites is also discussed. It is vital to understand how the addition of CNTs in a polymer composite alters the microstructure at the micro- and nano-scale, as well as how these modifications influence overall structural behavior, not only in its as fabricated form but also its functionalization techniques. The technological superiority gained with CNT addition to polymer composites may be advantageous, but scientific values are here to be critically explored for reliable, sustainable, and structural reliability in different industrial needs.

Chong Soo Park

Papers

Functionalization of carbon nanotubes for fabrication of CNT/epoxy nanocomposites