Poly SWCNT

Acyl chloride-functionalized SWCNTs are also susceptible to reactions with other nucleophiles, e.g. alcohols. Haddorfs group reported the preparation of soluble ester-functionalized carbon nanotubes SWCNT-COO(CH2)17CH3 (Fig. 1.6a) obtained by esterification with octadecanol [134]. The syntheses of soluble polymer-bound and dendritic ester-functionalized SWCNTs have been reported by Riggs et al. by attaching poly(vinyl acetate-co-vinyl alcohol) (Fig. 1.6b) [135] and hydrophilic and lipophilic dendron-type benzyl alcohols [119], respectively, to SWCNT-COC1 (Fig. 1.6c). These functional groups could be removed under basic and acidic hydrolysis conditions and thus additional evidence for the nature of the attachment was provided [119, 136]. 

Homopolymer PS and block copolymer poly(tert-butyl acrylate)-b-styrene, prepared by nitroxide-mediated living free-radical polymerization, were utilized for the functionalization of shortened SWCNTs through a radical coupling reaction (Scheme 1.33) [194]. 

Norbornene polymerization was initiated selectively on the surface of SWCNTs via a specifically adsorbed pyrene-linked ring-opening metathesis polymerization initiator (Fig. 1.20). The adsorption of the organic precursor was followed by cross-metathesis with a ruthenium alkylidene, resulting in a homogeneous noncovalent poly (norbornene) (PNBE) coating [249]. 

The enzymatic activity of a-chymotiypsin was evaluated in composites of poly(methyl metacrilate) with different carbon materials [91] demonstrating that the incorporation of SWCNTs into enzyme-polymer composites results in active and stable polymeric films. The release of the protein from the composite was evaluated measuring the enzymatic activity in the supernatant in contact with the composite. The results showed that in the case of SWCNTs the leaching of the protein from the composite was lower. This fact was attributed to the imion of the protein to the CNTs. The effect of other polymers such as polystyrene and poly(lactic acid) was also analyzed and the leaching of the protein was significant in the absence of SWCNTs. Only the hydrophobic ones (poly(methyl metacrilate)... 

Li and Niu et al. [69] employed the BmimPF -supported SWCNT electrode to execute electrografting poly(V-succinimidyl acrylate) (PNSA) onto their surfaces. 

Hitherto, there have also been some reports on the use of polymers containing ionic moieties except for polymeric ILs to functionalize CNTs [127-130]. For instance, Yoshida et al. [128] found that a slightly concentrated solution (20 g/L) of an ionic electrolyte of poly(pyridinium-l,4-diyl-iminocarbony 1-1,4-phenylene-methylene chloride) was most appropriate for stable dispersion of SWCNTs in water to form a SWCNT-containing gel. This ionic polymer, capable to act both as a dispersant and as a gelator, may contribute to the development of a novel hydrogel filled with CNTs for the biological, medical, and pharmaceutical applications. 

Alcohol dehydrogenase SWCNT/ poly(dimethyl diallylammonium chloride) (PDDA) modified GCE Ethanol biosensor [112]... 

The polyanion immobilized by noncovalent interactions onto SWCNTs (SWCNT-PSS ) was then able to anchor the octapyridiumporphyrin salt by strong electrostatic interactions. Porphyrins can also be immobilized onto CNTs by polymer wrapping through hydrophobic or tt-tt interactions in one example, poly(methyhnethacrylate) with grafted porphyrins was polymerized around the CNTs [38,52],... 

The success of FET-based CNT gas sensors quickly attracted interest for use in biosensing applications, particularly since biomolecules such as DNA and proteins are heavily charged under normal conditions. SWCNT FETs are expected to be more sensitive than chemisorbed gas molecules to the binding of such charged species. However, the wet chemical environment with the presence of various ions and other biomolecules makes it much more complicated than gas environments. Studies demonstrated that proteins in the solution tend to adsorb irreversibly onto the bare CNT surface and induce significant change in FET characteristics [67,68]. Thus, extensive efforts have been made to passivate CNT with various polymers, such as PEI, poly(ethylene glycol) (PEG), Nafion, or Tween 20 [67,69,70]. It is conunonly accepted that a polymer or surfactant... 

Figure 11.12 Structures of ionic dispersants of SWCNT in aqueous media and poly(m-phenylenevinylene) (PmPV) dispersant for SWCNT in chloroform.

PNMA, poly(N-methylaniline) PANI, poly(aniline) PEDOT, poly(3,4-ethylenedioxythiphene PSS, poly(styrene-sulfonate), PPy, poly(pyrrole) PEO, poly(ethylene oxide) DBSA, dodecylbenzene sulfonic acid CSA, camphor sulfonic acid PTSA, poly(o-toluene sulfonic acid) PFOA, perfluoro-octanolc acid TSA, toluene sulfonic acid CNF, carbon nanofiber SWCNT, single-walled carbon nanotube NP, nanoparticle MWCNT, multiwalled carbon nanotube PTh, poly(thlphene) CNT, carbon nanotube POA, poly(o-anisidine) SPANI, poly(anilinesulfonlcacld) PB, Prussian Blue DAB, 1,2-diamino benzene POEA, poly(o-ethoxyanlllne) PMMA, poly(methyl methacrylate). 

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