Composites CNT-based

Since the discovery of SWNTs, they have been expected to become the building blocks of the next generation of functional nanomaterials. However, their strong cohesive property and poor solubility have restricted the use of SWNTs for fundamental and applied research fields. One method to overcome these problems is to make the SWNTs more soluble by wrapping them with polymers [31]. At the same time, the fabrication of high-performance carbon nanotube (CNT)-based composites is driven by the ability to create anisotropy at the molecular level to obtain appropriate functions. 

EDS), SEM and TEM analysis [70]. The method allowed different organo-func-tional groups to be attached to MWCNTs, improving their compatibility with specific polymers for producing CNT-based composites. 

Nanocomposites with good thermal conductivity (k) have potential applications in printed circuit boards. The thermal conductivity of connectors is in the order of 103 W/(m-K), while typical thermoplastics have k 0.1 W/(m K). A theoretical model was proposed by Nan et al. to predict the thermal conductivity of CNT-based composites (75,76). Theoretically, the thermal conductivity of the composites filled with 0.1 wt% MWNTs can be six times that of neat polymers. 

Cost-Benefit Analysis of Conventional Foil Gauges vs. CNT-Based Composite Gauges... 

The proposed CNT-based composite gauge in this case study is assumed to be a thin film of a flexible thermoplastic polymer to which the CNTs are added and dispersed using the techniques described in (37,48). The produced thin film is then cut into small dimensions equivalent to those of conventional foil gauges. The cost of CNT-based film strain gauge is based on the material cost of a film of 15 mm x 50 mm x approximately 0.15 mm thickness using a density of PMMA = 1.2 g/cc, density of SWNT = 1.4 g/cc and density of MWNT = 1.9 g/cc. Table 15.4 summarizes the properties of the materials used. 

Feasibility of Using CNT-Based Composites in Aerospace Applications... 

In order to continue the development of intriguing CNT-based composites, three main challenges are being addressed ... 

The significant effect of shortening has been possibly underestimated so far in research on the properties of melt mixed CNT-based composites and should be taken into consideration in further studies on that topic. This was certainly due—in part—to the difficulties to measure the length after processing. However, the presented study clearly shows a way to measure the length as the importance to consider this quantity. 

Several PANl-CNT-based composites have been developed to detect neurotransmitters such as DA. Oxidative approaches... 

In 2012, G. H. Kim et al. prepared Gp-filled PEDOT PSS composite films via solution spin coating method [3]. XPS and Raman analyses identified that strong tt-tt interactions existed between Gp and PEDOT PSS, which facilitated the dispersion of Gp in the polymer matrix and reduced the carrier hopping barrier. The uniformly distributed Gp increased the interfacial area by 2-10 times as compared with CNT based composite on the same weight percentage. Moreover, well-stacked multilayer structure... 

FIGURE 4 Three loading cases for the cylindrical RVE used to evaluate the effective material properties of the CNT-based composites, (a) under axial stretch DL, (b) under lateral uniform load P, and (c) under torsional load T [56]. 

Akin to CNT-based composites, graphene has also been used for making composites with novel properties due to its reasonable mechanical, thermal, electrical properties and large smface area [26,327-330]. 

In this regard, composite materials are mainly encountered in the components of aerospace vehicles because they can be easily modulated to assess all of these demands. Carbon-nanotube (CNT)-based composites have received attention because of their specific properties such as (1) superior mechanical properties, (2) high thermal properties, and (3) electric properties [144]. The use of CNTs in aerospace... 

Carbon nanotubes possess a combination of good thermal, mechanical, and electrical properties that maJse them an excellent candidate for the fabrication of multifunctional polymer nanocomposites. The CNTs are stronger than steel and lighter than aluminum, thus the mechanical reinforcement of nanotubes for the polymer/CNT based composites is one of the most investigated fields. 

Due to the difTiculties encountered in experimental characterization of nanomaterial, theoretical approaches in determining the CNT-based composite properties have attracted a great interest. A tremendous amount of research has been developed to understand the mechanical behavior of CNTs and their composites. According to the literature, the theoietieal and computational approaches can be mainly classified into two categories i) atomistic modeling, and ii) continuum mechanics approaches [152-164] (see Fig. 23.12). 

Computational approach can play an important role in the development of the CNT-based eomposites by providing simulation results to help on the understanding, analysis and design of sueh nanocomposites. At the nanoscale, analytical models are difficult to establish or too complicated to solve, and tests are extremely difficult and expensive to eonduct. Modeling and simulations of nanoeomposites, on the other hand, ean be achieved readily and eost effectively on even a desktop computer. Characterizing the meehanieal properties of CNT-based composites is just one of the many important and urgent tasks that simulations can follow out [72]. 

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