Polymer-functionalized nanotubes

Interesting thermal response of the polystyrene nanocomposites was reported when untreated and polystyrene grafted nanotubes were used for the reinforcement of polymer (49). The glass transition temperature of the pure polystyrene matrix was observed to be 99 °C. Similar transition temperature of 98 °C was observed for the composites containing 2.5 vol% of the untreated nanotubes. The nanocomposites containing polymer functionalized nanotubes... 

The grafting-from approach is based on the mitial immobilization of initiators onto the nanotube surface, followed by in situ polymerization with the formation of the polymer molecules bound to the nanotube. The benefit of this technique is that polymer-functionalized nanotubes with high grafting density can be prepared. However, this method requires a strict control of the amoimts of initiator and substrate [53, 54]. The grafting- from technique is also used for the preparation of styryl-grafted nanotubes [55]. In this work, the carboxylic acid groups on the surface of oxidized MWNTs have been reacted with 4-vinyl-benzyl chlorides via an esterification reaction followed by the polymerization to produce polystyrene (PS)-grafted CNTs [34,36-38]. 

The reaction between toluene 2,4-diisocyanate and carboxylated MWCNTs afforded amido-functionalized nanotubes containing highly reactive isocyanate groups on their surface (Scheme 1.4). The amount of the isocyanate groups was determined by chemical titration and thermogravimetric analysis (TGA) [105]. The modified tubes may constitute promising components to prepare polymer-nanotube composites and coatings [106]. 

Wang X, Liu H, Jin Y, Chen C. Polymer-functionalized multiwalled carbon nanotubes as lithium intercalation hosts. J Phys Chem B 2006 110 10236-10240. 

Tseng et al. (51) reported the epoxy nanocomposites in which the nanotubes were functionalized by maleic anhydride by using plasma treatment. The thermal decomposition temperature was reported to increase with increasing the extent of the nanotubes in the composites as shown in Figure 2.16a. Untreated nanotubes were also used to reinforce the polymer and the increase in the decomposition temperature was also observed in this system as a function of filler content, but the enhancement was more significant using the functionalized nanotubes. This was attributed to... 

The presence of CNT in polymerization system not only changes properties of the polymer matrix but also has a significant impact onto carbon nanotubes they can be functionalized on the surface by the radicals. Functionalized nanotubes are on the one hand better individualized from the bundles and aggregates (44), but on the other hand they are shorter and can possess some open ends (43). 

Poly(ethylene terephthalate) functionalized with hyperbranched polyamine cations was prepared by Rao [3] and used to splay layered materials in a matrix in polymer-layered nanotubes. 

Li et al. studied the quality and activity of a catal3Tic system used in carbon nanotube (CNT) growth process using pRS [11]. By localized Raman mapping, the variation of the active metallic species (Fe, Co) over the oxide surface (CaCOs) was quantified and analyzed. In this study, it was observed that the compositional variation in the active species over the oxide surface affected the yield and morphology of the CNT. Mayo et al. employed pRS to study the phase separation of polymer-functionalized single-walled carbon nanotubes (SWCNTs) within... 

Mayo JD, Behai S, Adronov A (2009) Phase separation of polymer-functionalized SWNTs within a PMMA/Polystyrene blends. J Poiym Sci Poiym Chem 47 450-458 Cou JY, Lensch-Falk JL, Hemesath ER, Lauhon LJ (2009) Vanadium oxide nanowire Phase and orientation analyzed by Raman spectroscopy. J Appl Phys 105 034310-1-034310-6 Wang ZL (2004) Functional oxides nanobelts-materials, properties and potential applications in nanosystems and biotechnology. Annu Rev Phys Chem 55 159-196 Bliznyuk VN, Singamaneni S (2009) Polymer carbon nanotube composites. Encyclopedia of nanoscience and nanotechnology, (2012), ASP, Ed. H. S. Nalwa... 

Zhu J, Peng HQ, Rodriguez-Macias F, Margrave JL, Khabashesku VN, Imam AM, Lozano K, Barrera EV (2004) Reinforcing epoxy polymer composites through covalent integration of the functionalized nanotubes. Adv Funct Mater 14 643-648... 

Yang YK, Xie XL, Mai YW (2011) Functionalization of carbon nanotubes for polymer nanocomposites. In McNally T, Potschke P (eds) Polymer caibon nanotube composites synthesis, properties and applications. Woodhead, Cambridge... 

Shim, M., Javey, A., Kam, N. W. S. and Dai, H. J. (2001) Polymer functionalization for air-stable n-type carbon nanotube field-effect transistors . Journal of the American Chemical Society, 123(46), 11512-11513. 

Linear Polymer-functionalized Carbon Nanotubes (CNTs)... 

Figure 5.23 Representative TEM image of hyperbranched poly[3-ethyl-3-(hydro-xymethyl)oxetane]-grafted MWCNT with 87 wt% of polymer at the straight (a) and bend area of a functionalized nanotube (b). SEM images of HP-grafted MWCNT with 74 wt% of polymer (c) and pristine MWCNTs (d). Reprinted with permission from Xu et...

Zhu, J., Peng, H., Rodriguez-Macias, R, Margrave, J., Khabashesku, V. Imam, A., Lozano, K., and Barrera, E. Reinforcing epoxy polymer composites through covalent integration of functionalized nanotubes. Advanced Functional Materials, 14(7), 643-648 (2004). 

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