Polyethylene carbon nanotube

T. Tao, L. Zhang, J. Ma, C. Li, Production of flexible and electrically conductive polyethylene-carbon nanotube shish-kebab structures and their assembly into thin films, Ind. Eng. Chem. Res, vol. 51, pp. 5456-5460, 2012. 

Polyethylene carbon nanotube Electrical conductivity and rheological properties 18... 

Bonduel D, Bredeau S, Alexandre M, Monteverde F, Dubois P (2007) Supported metallocene catalysis as an efficient tool for the preparation of polyethylene/carbon nanotube nanocomposites effect of the catalytic system on the coating morphology. J Mater Chem... 

Xie, X.L., Aloys, K., Zhou, X.P., Zeng, F.D. Ultrahigh molecular mass polyethylene/ carbon nanotube composites - crystallization and melting properties , J. Therm. Anal. Calorim. 74(1) (2003), 317-323... 

S. Kanagaraj, F. R. Varanda, T. V. Zhil tsova, M. S. a. Oliveira, and J. a. O. Simoes. Mechanical properties of high density polyethylene/carbon nanotube composites. Compos. Sci. Technol. 67 (15-16), 3071-3077 (December, 2007). 

Y. Wang, R. Cheng, and L. Liang. Study on the preparation and characterization of ultra-high molecular weight polyethylene/carbon nanotubes composite fiber. Compos. Sci. Technol. 65 (5), 793-797 (April, 2005). 

B. M. Amoh, S. A. A. Ramazani, and H. Izadi. Preparation of Ultrahigh-Molecular-Weight Polyethylene / Carbon Nanotube Nanocomposites with a Ziegler - Natta Catalytic System and Investigation of Their Thermal and Mechanical Properties. /. Appl. Polym. Sci. 125, E453 (2012). 

S. Kanagaraj, A. Fonseca, R. M. Guedes, M. S. A. Ohveira, and J. A. O. Simoes, Thermo-Mechanical Behaviour of Ultrahigh Molecular Weight Polyethylene-Carbon Nanotubes Composites under Different Cooling Techniques. Defect Diffus. Forum. 312-315, 331-340 (April, 2011). 

Goh HW, Goh SH, Xu GQ, Lee KY, Yang GY, Lee YW, Zhang WD (2003). Optical limiting properties of double-C60-end-capped poly(ethylene oxide), double-C -end-capped polyethylene oxide)/poly(ethylene oxide) blend, and double-C -end-capped poly(ethylene oxide)/multiwalled carbon nanotube composite. J. Phys. Chem. B 107 6056-6062. 

As with fullerenes, carbon nanotubes are also hydrophobic and must be made soluble for suspension in aqueous media. Nanotubes are commonly functionalized to make them water soluble although they can also be non-covalently wrapped with polymers, polysaccharides, surfactants, and DNA to aid in solubilization (Casey et al., 2005 Kam et al., 2005 Sinani et al., 2005 Torti et al., 2007). Functionalization usually begins by formation of carboxylic acid groups on the exterior of the nanotubes by oxidative treatments such as sonication in acids, followed by secondary chemical reactions to attach functional molecules to the carboxyl groups. For example, polyethylene glycol has been attached to SWNT to aid in solubility (Zhao et al., 2005). DNA has also been added onto SWNT for efficient delivery into cells (Kam et al., 2005). 

CNTs may consist of just one layer (i.e. single-walled carbon nanotubes, SWCNTs), two layers (DWCNTs) or many layers (MWCNTs) and per definition exhibit diameters in the range of 0.7 < d < 2 nm, 1 < d < 3 nm, and 1. 4 < d < 150 nm, respectively. The length of CNTs depends on the synthesis technique used (Section 1.1.4) and can vary from a few microns to a current world record of a few cm [16]. This amounts to aspect ratios (i.e. length/diameter) of up to 107, which are considerably larger than those of high-performance polyethylene (PE, Dyneema). The aspect ratio is a crucial parameter, since it affects, for example, the electrical and mechanical properties of CNT-containing nanocomposites. 

P. Lemoine, J. P. Quinn, Polyethylene multiwalled carbon nanotube composites, Polymer, vol. 46, p. 8222-8232, 2005. 

Logakis E, Pissis P, Pospiech D, Korwitz A, Krause B, Reuter U, et al. Low electrical percolation threshold in polyethylene terephthalate)/multi-walled carbon nanotube nanocomposites. European Polymer Journal. 2010 May 46(5) 928-36. 

Wenzhoug Tang, Michael H. Santare, Suresh G. Advani. Melt processing and mechanical property characterization of multi-walled carbon nanotube/ high density polyethylene (MWNT/HDPE) composite films. Carbon 2003 41 2779-2785. 

Figure 12.15). In the case of MWNTs, the shift to higher frequencies was explained by a disentanglement of the carbon nanotubes and a subsequent dispersion in the polymer as a consequence of polymer penetration into the bundles during solution mixing. An up-shift of 17 cm-1 for the G band, obtained on addition of 1 wt% MWNTs in a polyethylene matrix, was considered as a consequence of strong compressive forces associated with polymer chains on MWNTs (87). 

Nakayama-Ratchford N, Bangsaruntip S, Sun X et al (2007) Noncovalent functionalization of carbon nanotubes by fluorescein-polyethylene glycol supramolecular conjugates with pH-dependent absorbance fluorescence. J Am Chem Soc 129 2448-2449... 

Water soluble carbon nanotubes can be produced by attaching polyethylene glycol units to the carboxyl groups (Figure 3.67). In this way, it has been possible to dissolve several hundreds of milligrams in one milliUter of water. Useful derivatives can be prepared by reacting the carboxyl units at the ends of the tubes. One example are tips for a chemosensitive AFM (Section 3.6.1.1). 

Even simple polymers like polyethylene or polypropylene can form composites with carbon nanotubes. The embedding, however, is limited to noncovalent interaction due to the complete lack of functional groups. Yet on the other hand, the hydrophobic nanotube surface hardly poses any problems in a wetting by the nonpolar polymer chains or in the formation of noncovalently bound composites. 

Interesting supramolecular structures can furthermore be obtained by the controlled crystallization of polymers hke polyethylene or nylon-6,6 on carbon nanotubes. The latter serve both as template and as nucleus of crystallization. There are in principle three modes of how a polymer crystal might grow on a nanotube surface (a) Phase separation may occur in the course of the crystallization so the initially dispersed carbon nanotubes rea omerate and precipitate, (b) The polymer coils around the individual tubes whose solubility increases in the sequel,... 

Carbon nanotubes functionalized with organic residues can act as sensors, too. For example, the limit of detection of NO2 drops below 100 ppt using nanotubes modified with polyethylene imine. Strongly electron-withdrawing molecules as well can be detected this way. Sensors consisting of nanotubes may further... 

Zhang, et al, Interfacial Characteristics of Carbon Nanotube-Polyethylene Composites Using Molecular Dynamics Simulations, ISRN Materials Science, Article ID 145042,2011. 

The polyethylene system, a loosely connected bond network, was chosen as a worst possible case in order to illustrate the limitations of classical MD simulation. Systems with external constraints (such as nearby chains in a crystal) or cyclical bond networks would be expected to exhibit significantly restricted motion. In fact, classical simulations of carbon nanotubes, which have a two-dimensional bond network, showed a sizeable but significantly smaller disagreement with quantum results. 

Shaheer Akhtar, M., Park, J. G., Lee, H. C., Lee, S. K., Yang, 0. B. (2010). Carbon nanotubes-polyethylene oxide composite electrolyte for solid-state dye-sensitized solar cells, Electrochim. Acta. 55(7), 2418-2423. 

Uddin, N. M., Capaldi, F. M., Farouk, B. (2011). Molecular dynamics simulations of the interactions and dispersion of carbon nanotubes in polyethylene oxide/water systems. Polymer. 52(2), 288-296. 

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