Fullerenes glasses

Another route to fabricate fullerene doped monoliths has been shown by Peng et al. (2001), which successfully prepared crack free, transparent fullerene glasses oflarge dimensions (up to 60 mm) from sol-gel mixtures of aminated Cgo derivatives and tetraethyl orthosilicate (TEOS). The aminated fullerene derivatives have been synthesized by amination reactions of Ceo with 6-amino-l-hexanol, cyclohexylamine, 2-(2-aminoethoxy)ethanol, and 3-aminopropyltriethoxysilane to prepare derivatives with the molecular structures H C6o[NH(CH2)6oH]jt, H C6o(NH-cyc/o-C6Hn)je, Hjj,C6o[NH(CH2CH2o)2H], and H (C6o[NH(CH2)3Si(OCH2CH3)3]i . A silica network with covalently bonded amine fullerene derivatives has been obtained, as shown in Figure 23-3. 

Below 90 K, [60]fullerene freezes into an orientational glass in which it adopts a simple cubic stmcture [19]. This low temperature stmcture can be traced to the anisotropic electronic stmcture. Alignment of the electron rich regions of... 

Researchers smdied the effect of fullerene in rubber composites with different temperature range [52]. There was no substantial influence of fullerene on Tg, tan 8, and G-modulus within the temperamre range from — 150°C to —50°C (glassy state), and properties increase at mbbery state (0°C-150°C). At temperamres between — 150°C and —50°C when rubber is rigid, G-modulus is virtually independent of the fullerene concentrations between 0.065 and 0.75 phr and a single major peak in Figure 28.26 shows that the fullerene does not influence the glass transition. 

The friction and wear properties of fullerene LB fihns have been investigated. The coefficient of kinetic friction was measured using a steel ball-on-glass disk method, with the LB films deposited onto the glass disk [326,327]. The friction coefficient dropped from 0.8... 

After addition of solutions of fullerenes C60 or fulleiene C60-containing composites to the cell medium, the concentration of silicon dioxide was 0.02%, and that of fullerenes C60 - 10 5 M. Samples were placed in a glass tube and irradiated for 2 min by mercury-vapor lamp (power 24 W) at the distance of 5 cm. 

Figure 22. Human embryonic kidney cells (A), rat vascular smooth muscle cells (B, C) and human osteoblast-like MG 63 cells (D) in cultures on micropattemed surfaces. A, B PTFE irradiated with UV light produced by a Xe2 -excimer lamp for 30 min in an ammonia atmosphere through a mask with holes 100 pm in diameter and center-to-center distance 300 pm C PE irradiated with Ar ions (energy 150 keV, ion dose lO ions/cm ) through a mask with holes 100 pm in diameter and center-to-center distance 200 pm fullerenes Qo deposited through a mask with rectangular holes with an average size of 128 3 pm per 98 8 pm on glass coverslips. Day 7 after seeding. A native cells in an inverted phase-contrast microscope B, C cells stained with hematoxylin and eosin, Olympus microscope IX 50 D cells stained with fluorescence-based LIVE/DEAD viability/cytotoxicity kit (Invitrogen), Olympus microscope IX 50. Bars 300 pm (A), 200 pm (B, D), Imm (C) [10,11].

Figure 29. Fiuman osteoblast-like MG 63 cells in cultures on material surfaces modified with carbon nanoparticles. A fullerene Cgo layers deposited on carbon fibre-reinforced carbon composites (CFRC), B fullerene C o layers deposited on microscopic glass coverslips, C terpolymer of polytetrafluoroethylene, polyvinyldifluoride and polypropylene, mixed with 4% of single-wall carbon nanohorns, D the same terpolymer with high crystalline electric arc multi-wall nanotubes, E diamond layer with hierarchically organized micro- and nanostmcture deposited on a Si substrate, F nanocrystalline diamond layer on a Si substrate. Standard control cell culture substrates were represented by a PS culture dish (G) and microscopic glass coverslip (FI). Immunofluorescence staining on day 2 (A) or 3 (B-Fl) after seeding, Olympus epifluorescence microscope IX 50, digital camera DP 70, obj. 20x, bar 100 pm (A, C, D, G,H)or 200 pm (B, E, F) [16].

Fullerenes can also be produced by direct inductive heating of a carbon sample held in a boron nitride support [43]. Evaporation at 2700 °C in a helium atmosphere affords fullerene-containing soot that is collected on the cold Pyrex glass of the reaction tube. This method allows a continuous operation by keeping the graphite... 

The CgQ surface coverage was determined to be 2.0 10 mol cm . The monolayer can be further modified with monomeric amine reagents, which demonstrates the potential of the self-assembly process for growing three-dimensional fullerene structures. Different surfaces such as quartz. Si-oxide [105] or ITO [102] were coated with multilayers of fullerene up to stacks of 9 layers. An imidirectional electron transfer is possible across the fullerene mulhlayers [102]. Not only can multiple layers of fullerenes be connected to a certain surface but amino-functionalized can also serve as a linker between two different surfaces. 3-Aminopropyl-tethered glass plates could be linked via a Cgg layer to 3-aminopropyl covered zeolite crystals [106]. 

Fig. 5.2 Pristine fullerene powder (1), medium strong hydrogenation (2), hydrogenation to maximal level (up to at least C6ffH30, Talyzin et al. 2006b) (3), and glass like sample obtained after hydrogenation experiment shown in Fig. 5.1 (Talyzin et al. 2004a) which consists mostly from products of hydrogenation-induced collapse of fullerene molecules (4)...

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