Effects of dispersion surfactants on the properties of ceramic–carbon nanotube (CNT) nanocomposites

Abstract

Gum Arabic (GA), Sodium Dodecyl Sulfate (SDS) and their mixture were used for the dispersion of multi-walled carbon nanotubes (CNTs) in an alumina matrix. A good dispersion at low loadings (0.5-1 wt%) of CNTs in alumina was achieved by an ultrasonic bath treatment. Dispersions were evaluated by UV-vis spectroscopy and agglomerate size analysis. The mixture of GA and SDS produced good dispersion as compared to GA and SDS alone. Nanocomposite powders were sintered by Spark Plasma Sintering (SPS). Microstructural, electrical and mechanical characterizations of sintered discs were carried out to evaluate the effectiveness of the different dispersants. The mixture of GA and SDS produced homogeneous and agglomerate-free CNT-alumina nanocomposites with higher electrical conductivity and indentation fracture toughness as compared to nanocomposites prepared using GA and SDS alone.

Structural health monitoring capabilities in ceramic–carbon nanocomposites

“…This is primarily due to the lubricant nature of carbon nanofillers which is responsible for deeper penetration on the Vickers indenter during the indentation. These observations for the hardness of nanocomposites are in consistent with the studies conducted by different groups [3,7,[37][38]. It is interesting to note that there is no significant difference in hardness for the different types of nanocomposites.…”

Comparative studies on Graphite and Carbon Black powders, and their dispersions

“…Therefore, rigorous stirring of CNTs in polymer matrix give fine dispersion of CNT [28][29][30]. As there has been substantial studies on the degree of dispersion of CNTs and Graphene [25,[31][32][33][34][35][36] but limited investigation on the dispersion behaviour of CB [17,20] and Graphite [37][38][39] in different solvents, the present research work focuses on the latter using two solvents. Here, carbon (mainly, CB and Graphite) dispersions in two different solvents (DMF and DMSO 4 ) were examined for particle size distribution and structural information using Laser Particle Size Analyzer and XRD, 5 respectively.…”

“…These augmented stable polymeric dispersions have applications in pigments of ink-jet printers [18,19]. Generally, the surfactants used for preparing stable dispersions of carbon powder particles are poly-dimethylsiloxane [20], Orotan® -a polyacrylate [21], sodium dodecylbenzenesulfonate, DMF 2 [22], sodium dodecyl sulphate [23][24][25]. Generally, CB as well as Graphite easily agglomerate in hydrophilic solvents and liquid media not having right range of cohesive energies, due to their inherent hydrophobic nature.…”

An experimental study on thermal characteristics of nanofluid with graphene and multi-wall carbon nanotubes

“…Graphene (GN) has two-dimensional extended honeycomb network of sp 2 hybridized carbon atoms [17], high electron mobility [18], excellent mechanical and chemical properties [19], high thermal conductivity (5000 W/(m·K)) [20] and twice particular surface area compared with SWCNTs [11], whereas CNTs, first made in the early 1990s [21], carry some features such as one of the lightest [22], strongest [23], stiffest [23], electrically conductive [24−25] nanoparticles with thermal conductivity of 3500 W/(m·K) [26]. Moreover, individual CNTs have ON/OFF current ratios higher than 10 5 [27] and carry three orders of magnitude higher current than copper [28].…”