Recent Developments in Carbon Nanotubes-Reinforced Ceramic Matrix Composites: A Review on Dispersion and Densification Techniques

Ceramic matrix composites (CMCs) are well-established composites applied on commercial, laboratory, and even industrial scales, including pottery for decoration, glass–ceramics-based light-emitting diodes (LEDs), commercial cooking utensils, high-temperature laboratory instruments, industrial catalytic reactors, and engine turbine blades. Despite the extensive applications of CMCs, researchers had to deal with their brittleness, low electrical conductivity, and low thermal properties. The use of carbon nanotubes (CNTs) as reinforcement is an effective and efficient method to tailor the ceramic structure at the nanoscale, which provides considerable practicability in the fabrication of highly functional CMC materials. This article provides a comprehensive review of CNTs-reinforced CMC materials (CNTs-CMCs). We critically examined the notable challenges during the synthesis of CNTs-CMCs. Five CNT dispersion processes were elucidated with a comparative study of the established research for the homogeneity distribution in the CMCs and the enhanced properties. We also discussed the effect of densification techniques on the properties of CNTs-CMCs. Additionally, we synopsized the outstanding microstructural and functional properties of CNTs in the CNTs-CMCs, namely stimulated ceramic crystallization, high thermal conductivity, bandgap reduction, and improved mechanical toughness. We also addressed the fundamental insights for the future technological maturation and advancement of CNTs-CMCs.

The Influence of DMDBS on Crystallization Behavior and Crystalline Morphology of Weakly-Phase-Separated Olefin Block Copolymer

Olefin block copolymer (OBC), with its low hard segments, can form unique space-filling spherulites other than confined-crystallization morphologies, mainly due to its weak phase-separation. In this work, 1,3;2,4-Bis(3,4-dimethylbenzylidene) sorbitol (DMDBS), a well-known nucleating agent, was used to tailor the crystallization behavior and crystalline morphology of OBC. It was found that DMDBS can precipitate within an OBC matrix and self-assemble into crystalline fibrils when cooling from the melt. A non-isothermal crystallization process exhibited an increased crystallization rate and strong composition dependence. During the isothermal crystallization process, DMDBS showed a more obvious nucleating efficiency at a higher crystallization temperature. OBC showed typical spherulites when DMDBS was added. Moreover, a low addition of DMDBS significantly decreased the crystal size, while a large addition of DMDBS induced aggregates, due to the limited miscibility of DMDBS with OBC. The efficient nucleating effect of DMDBS on OBC led to an increased optical transparency for OBC/DMDBS composites.

Exploring the effects and mechanisms of carbon nanomaterial diversity on the morphology of lysozyme crystals

A shift in the final size distribution and morphology was observed, and more pronounced X-ray diffraction peaks were achieved in lysozyme crystals with the addition of 3D CNMs.

Excellent mechanical performance and enhanced dielectric properties of OBC/SiO2 elastomeric nanocomposites: effect of dispersion of the SiO2 nanoparticles

A chain-like network structure and irregular dispersion of fillers are formed in OBC/SiO₂ nanocomposites. Excellent mechanical performance and enhanced dielectric properties of OBC/SiO₂ elastomeric nanocomposites are realized due to the peculiar chain-like network of the fillers.

Enhanced mechanical properties of olefin block copolymer by adding a quaternary ammonium salt functionalized graphene oxide

Large mechanical properties enhancement of OBC via blending with chemical modification CTAB-GO.

The effect of hard block content on the orientation and mechanical properties of olefin block copolymer films as obtained via melt stretching

In this study, the orientation, structure and mechanical performance of a series of uniaxially oriented films based on olefin block copolymers (OBC) have been investigated in terms of the differences in hard block content and draw ratio (DR).

Liquid–solid transition in mesophase separated olefin multiblock copolymers during crystallization

A delayed liquid–solid transition has been found in strongly segregated olefin multiblock copolymers, compared to that in weakly segregated systems.

Effect of melting temperature on interfacial interaction and mechanical properties of polypropylene (PP) fiber reinforced olefin block copolymers (OBCs)

Transcrystalline structures for the first time were observed at the interface of OBC/PP fiber, proving that the partially melted (170 °C) and totally melted (190 °C) PP fibers have stronger interactions with OBC than unmelted PP fibers does.