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Thermal cycling effects and governing mechanisms of a CNT latex nanocomposite film

International SAMPE Technical Conference

Briggs, Timothy B.; O'Bryan, Gregory O.; Loyola, B.R.; La Ford, M.; Yang, Elaine L.; Vance, Andrew L.; Skinner, J.L.

The thermal cycling effects as well as isothermal conditions on a conductive multi-walled carbon nanotube (MWCNT) filled latex film are presented and analyzed for a multi-day exposure period. Using a water-based latex solution, multi-walled CNT's have been doped within it and then applied with stencil masked spray deposition to the surface of a non-conductive manufactured substrate. Four-point probe resistivity measurements were conducted in-situ via electrodes deposited across the width of the latex film on the top surface via brush application. The temperature range of consideration was computer controlled using a nitrogen purged environmental chamber cycling between-50 to 80 °C with isothermal holds at each extrema. We have identified long term and short-term temperature-dependent resistivity trends as well as a correlation between environmental conditions and the effect on electrical properties of the nanocomposite.

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TYPE Conference YEAR 2012
ScopusOSTI

A novel method for homogenous dispersion of multi-walled carbon nano-tubes onto prepreg composite materials

International SAMPE Technical Conference

Briggs, T.M.; O'Bryan, Gregory O.; LaFord, Marianne L.; Vance, Andrew L.; Skinner, J.L.; Moody, Neville R.

In this study we report a novel method of dispersing multi-walled carbon nanotubes (MWCNTs) using an electrospinning depositional process onto a conventional, uncured preimpregnated composite material. The main focus is the determination of the process parameters in order to consistently and homogeneously disperse MWCNTs onto a secondary substrate. Due to the exceptional thermal, mechanical, and electrical properties that can be exploited in CNTs, a homogenous dispersion can lead to isotropy in material properties of interest-mechanical, thermal, electrical etc. By combining these materials with structural composite materials, the true spirit of a tailored engineering material can be exploited even further to induce specific properties that are desired for a particular application. Through the use of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images, as well as vertical scanning interferometry, the resulting electrospun fibers are imaged and correlated with process parameters.

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TYPE Conference YEAR 2012
ScopusOSTI

(E)-4-[(4-nitrophenyl)diazenyl]phenyl anthracene-9-carboxylate

Proposed for publication in Acta Crystallographica E.

Rodriguez, Marko A.; Zifer, Thomas Z.; Vance, Andrew L.; Wong, Bryan M.; Leonard, Francois L.

In the title compound, C{sub 27}H{sub 17}N{sub 3}O{sub 4}, the azo group displays a trans conformation and the dihedral angles between the central benzene ring and the pendant anthracene and nitrobenzene rings are 82.94 (7) and 7.30 (9){sup o}, respectively. In the crystal structure, weak C-H...O hydrogen bonds, likely associated with a dipole moment present on the molecule, help to consolidate the packing.

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TYPE Journal Article YEAR 2008
OSTI

Color detection using chromophore-nanotube hybrid devices

Proposed for publication in Nano Letters.

Zhou, Xinjian Z.; Zifer, Thomas Z.; Wong, Bryan M.; Krafcik, Karen L.; Leonard, Francois L.; Vance, Andrew L.

We present a nanoscale color detector based on a single-walled carbon nanotube functionalized with azobenzene chromophores, where the chromophores serve as photoabsorbers and the nanotube as the electronic read-out. By synthesizing chromophores with specific absorption windows in the visible spectrum and anchoring them to the nanotube surface, we demonstrate the controlled detection of visible light of low intensity in narrow ranges of wavelengths. Our measurements suggest that upon photoabsorption, the chromophores isomerize from the ground state trans configuration to the excited state cis configuration, accompanied by a large change in dipole moment, changing the electrostatic environment of the nanotube. All-electron ab initio calculations are used to study the chromophore-nanotube hybrids and show that the chromophores bind strongly to the nanotubes without disturbing the electronic structure of either species. Calculated values of the dipole moments support the notion of dipole changes as the optical detection mechanism.

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TYPE Journal Article YEAR 2008
OSTI
14 Results
14 Results