Carbon nanotubes reinforced plastics

Carbon nanotubes can be used in reinforcing polymer matrix composites in two ways a) as the sole reinforcing phase (CNTRP), or b) as an additional reinforcing phase in conjunction with carbon fibers (CF+CNT) in a hybrid composite. Carbon nanotubes reinforced plastics (CNTRP) can be prepared by several methods, as described in section 15.1.3. Both CFRP and CNTRP composite structures can be joined using structural adhesives but machining and drilling are difficult as a result of the widely different properties of their constituents. 

Some applications of carbon nanotube-reinforced plastics are tabulated in Table 7.5. 

Cansell, F. Aymonier, C. Loppinet-Serani, A. (2003) Review on Materials Science and Supercritical Fluids. Curr. Opin. Solid State Mater. Sci. Vol.7, No.4-5, pp.331-340 Chang, t. Jensen, L. Kisliuk, A. Pipes, R. Pyrz, R. Sokolov, A. (2005) Microscopic mechanism of reinforcement in single-wall carbon nanotube / polypropylene nanocomposites. Polym. Vol.46, No. 2,pp.439-444 Coleman, J. Cadek, M Blake, R. Nicolosi, V. Ryan, K Belton, C. Fonseca, A. Nagy, J. Gim ko, Y. Blau, W. (2004) High Performance Nanotube-Reinforced Plastics ... 

Wong E W, Sheehan P E and Lieber C M, Nanobeam mechanics elasticity, strength, and toughness of nanorods and nanotubes . Science, 1997 111 1971-1975. Kuzumaki T, Hayashi T, Ichinose H, Miyazawa K, Ito K and Ishida Y, Fine structure of plastically deformed carbon nanotube , J Jpn Inst Met, 1996 60(1) 9-15. Kuzumaki T, Hayashi T, Ichinose H, Miyazawa K, Ito K and Ishida Y, In situ observed deformation of carbon nanotubes , Philos Mag A, 1998 77(6) 1461-1469. Kuzumaki T, Miyazawa K, Ichinose H and Ito K, Processing of carbon nanotube reinforced aluminum composite , J Mater Res, 1998 13(9) 2445-2449. 

Other nano-fillers have also investigated. Cao et al. [253] reported the utilization of multiwalled carbon nanotubes (MWCNTs) as filler-reinforcement to improve the performance of plasticized starch (PS). The PS/MWCNTs nanocomposites were prepared by a simple method of solution casting and evaporation. The results indicated that the MWCNTs dispersed homogeneously in the PS matrix and formed strong hydrogen bonding with PS molecules. Besides the improvement of mechanical properties, the incorporation of MWCNTs into the PS matrix also led to a decrease in the water sensitivity of the PS-based materials. 

Recently, nanostructured carbon-based fillers such as Ceo [313,314], single-wall carbon nanotubes, carbon nanohorns (CNHs), carbon nanoballoons (CNBs), ketjenblack (KB), conductive grade and graphitized carbon black (CB) [184], graphene [348], and nanodiamonds [349] have been used to prepare PLA-based composites. These fillers enhance the crystalUza-tion ofPLLA [184,313,314].Nanocomposites incorporating fibrous MWCNTsandSWCNTs are discussed in the section on fibre-reinforced plastics (section 8.12.3). 

J. Al-Hawarin, A.S. Ayesh, and E Yasin, Enhanced physical properties of poly(vinyl alcohol)-based single-walled carbon nanotube nanocomposites through ozone treatment of single-walled carbon nanotubes. Journal of Reinforced Plastics and Composites, 32 (17), 1295-1301, 2013. 

Ryan K P, Cadek M, Nicolosi V, Blond D, Ruether M, Armstrong G, Swan H, Fonseca A, Nagy J B, Maser W K, Blau W J and Coleman J N (2007) Carbon nanotubes for reinforcement of plastics A case study with poly(vinyl alcohol). Compos Sci PecAnof 67 1640-1649. 

Typical reinforcing agents now commonly employed in the formation of plastics include glass fiber, carbon fiber, carbon nanotubes, carbon black, graphite, organically modified clay, talc, graphene, and fullerene. 

As discussed in Chapter 6, the incorporation of reinforcing agents or fillers into plastic formulations can, in some but not all cases, lead to variations in the molecular stability of plastics and also their thermal and thermooxidation stability. Thus, it has been observed that the addition of silica to polytetrafluoroethylene did not adversely affect polymer stability, while the incorporation of 25% of organically modified silica into polyethylene led to a decrease in weight loss of the plastic from 80% to 33.7%. The incorporation of carbon nanotubes in epoxy resins unproved their mechanical and thermal properties. It is fair to say that the effect of reinforcing agents on the thermal and thermooxidative stability of polymers must always be bom in mind when selecting polymer formulations for a particular application. 

Carbon nanotubes are being increasingly used for the reinforcement of plastics, including epoxy resins [57-59], polyamides [55, 60-62], polyimides [63], poly-silsesquioxane [64], polycaprolactam [65], polyethylene oxide [66], polyethylene [67, 55,62], polyurethane [67], ethylene-vinyl acetate [69-73], polyhydroxybutylene-co-hydroxyvalerate [75], ethylene-propylene diene terpolymer [73], and sulfonated polyarylene sulfone [53]. 

Many mechanical, electrical, thermal, and other properties, such as thermal stability, of plastics can be considerably improved by the incorporation of reinforcing agents, such as glass fiber, carbon fiber, carbon nanotubes, and many more fillers, such as talc and clay in their formulation. 

Polymer nanocomposites are a class of reinforced polymers produced by incorporating materials that have one or more dimensions on the nanometer scale (<100nm), such as layered silicates, carbon nanotubes, nanofibers, whiskers, ultrafine layered titanate, or inorganic-organic hybrid systems. Layered silicates (mainly montmorillonite (MMT) and hectorite) are the most commonly used nanomaterials in the plastics industry today owing to their availability and low... 

Lemes AP, Marcato PD, Ferreira OP, Alves OL, Duran N (2008) Nanotechnology and applications. In Nanocomposites of poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) reinforced with carbon nanotubes and oxidized carbon nanotubes, pp 615-085 Lenz RW, Marchessault RH (2005) Bacterial polyesters biosynthesis, biodegradable plastics and biotechnology. Biomacromolecules 6 1-8... 

Based on the procedures described in the previous sections, one can obtain nanomechanical maps of a wide variety of polymeric and biological materials, including carbon black (CB)-reinforced natural rubber (NR) [40], carbon nanotube (CNT)-reinforced NR [41,42], reactive polymer blend [43], block copolymers [9,21,44,45], deformed plastics [46,47], human hair [48,49], honeycomb-patterned polymer films [50-52], CNT-reinforced hydrogel [53], and diffusion front of polymer [54,55]. The detailed descriptions are also found in other literatures [56-59]. Hereafter, several example studies are reviewed. 

Flame-barrier coatings—Thin coatings composed of multi-walled carbon nanotubes dispersed in silicone matrices exhibit outstanding flame barrier characteristics (i.e., protection from combustion and decomposition). In addition, they offer abrasion and scratch resistance do not produce toxic gases and are extremely adherent to most glass, metal, wood, plastic, and composite surfaces. Hame-barrier coatings are used in aerospace, aviation, electronic, and industrial applications, and typically applied on wires and cables, foams, fuel tanks, and reinforced composites. 

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