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Title: Multiscale metrologies for process optimization of carbon nanotube polymer composites

Abstract

Carbon nanotube (CNT) polymer nanocomposites are attractive multifunctional materials with a growing range of commercial applications. With the increasing demand for these materials, it is imperative to develop and validate methods for on-line quality control and process monitoring during production. In this work, a novel combination of characterization techniques is utilized, that facilitates the non-invasive assessment of CNT dispersion in epoxy produced by the scalable process of calendering. First, the structural parameters of these nanocomposites are evaluated across multiple length scales (10 -10 m to 10 -3 m) using scanning gallium-ion microscopy, transmission electron microscopy and small-angle neutron scattering. Then, a non-contact resonant microwave cavity perturbation (RCP) technique is employed to accurately measure the AC electrical conductivity of the nanocomposites. Quantitative correlations between the conductivity and structural parameters find the RCP measurements to be sensitive to CNT mass fraction, spatial organization and, therefore, the processing parameters. These results, and the non-contact nature and speed of RCP measurements identify this technique as being ideally suited for quality control of CNT nanocomposites in a nanomanufacturing environment. In conclusion, when validated by the multiscale characterization suite, RCP may be broadly applicable in the production of hybrid functional materials, such as graphene, gold nanorod,more » and carbon black nanocomposites.« less

Authors:
ORCiD logo [1];  [2];  [3];  [4];  [1];  [5];  [5];  [5];  [4];  [5];  [5];  [5]
  1. National Institute of Standards and Technology, Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States)
  2. National Institute of Standards and Technology, Boulder, CO (United States)
  3. National Institute of Standards and Technology, Gaithersburg, MD (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Univ. of Delaware, Newark, DE (United States)
  5. National Institute of Standards and Technology, Gaithersburg, MD (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1324186
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Carbon
Additional Journal Information:
Journal Volume: 108; Journal Issue: C; Journal ID: ISSN 0008-6223
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Natarajan, Bharath, Orloff, Nathan D., Ashkar, Rana, Doshi, Sagar, Twedt, Kevin, Krishnamurthy, Ajay, Davis, Chelsea, Forster, Aaron M., Thostenson, Erik, Obrzut, Jan, Sharma, Renu, and Liddle, James Alexander. Multiscale metrologies for process optimization of carbon nanotube polymer composites. United States: N. p., 2016. Web. doi:10.1016/j.carbon.2016.07.028.
Natarajan, Bharath, Orloff, Nathan D., Ashkar, Rana, Doshi, Sagar, Twedt, Kevin, Krishnamurthy, Ajay, Davis, Chelsea, Forster, Aaron M., Thostenson, Erik, Obrzut, Jan, Sharma, Renu, & Liddle, James Alexander. Multiscale metrologies for process optimization of carbon nanotube polymer composites. United States. doi:10.1016/j.carbon.2016.07.028.
Natarajan, Bharath, Orloff, Nathan D., Ashkar, Rana, Doshi, Sagar, Twedt, Kevin, Krishnamurthy, Ajay, Davis, Chelsea, Forster, Aaron M., Thostenson, Erik, Obrzut, Jan, Sharma, Renu, and Liddle, James Alexander. 2016. "Multiscale metrologies for process optimization of carbon nanotube polymer composites". United States. doi:10.1016/j.carbon.2016.07.028. https://www.osti.gov/servlets/purl/1324186.
@article{osti_1324186,
title = {Multiscale metrologies for process optimization of carbon nanotube polymer composites},
author = {Natarajan, Bharath and Orloff, Nathan D. and Ashkar, Rana and Doshi, Sagar and Twedt, Kevin and Krishnamurthy, Ajay and Davis, Chelsea and Forster, Aaron M. and Thostenson, Erik and Obrzut, Jan and Sharma, Renu and Liddle, James Alexander},
abstractNote = {Carbon nanotube (CNT) polymer nanocomposites are attractive multifunctional materials with a growing range of commercial applications. With the increasing demand for these materials, it is imperative to develop and validate methods for on-line quality control and process monitoring during production. In this work, a novel combination of characterization techniques is utilized, that facilitates the non-invasive assessment of CNT dispersion in epoxy produced by the scalable process of calendering. First, the structural parameters of these nanocomposites are evaluated across multiple length scales (10-10 m to 10-3 m) using scanning gallium-ion microscopy, transmission electron microscopy and small-angle neutron scattering. Then, a non-contact resonant microwave cavity perturbation (RCP) technique is employed to accurately measure the AC electrical conductivity of the nanocomposites. Quantitative correlations between the conductivity and structural parameters find the RCP measurements to be sensitive to CNT mass fraction, spatial organization and, therefore, the processing parameters. These results, and the non-contact nature and speed of RCP measurements identify this technique as being ideally suited for quality control of CNT nanocomposites in a nanomanufacturing environment. In conclusion, when validated by the multiscale characterization suite, RCP may be broadly applicable in the production of hybrid functional materials, such as graphene, gold nanorod, and carbon black nanocomposites.},
doi = {10.1016/j.carbon.2016.07.028},
journal = {Carbon},
number = C,
volume = 108,
place = {United States},
year = 2016,
month = 7
}

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  • Dissipative Particle Dynamics (DPD) simulations were used to investigate methods of controlling the assembly of percolating networks of carbon nanotubes (CNTs) in thin films of block copolymer melts. For suitably chosen polymers the CNTs were found to spontaneously self-assemble into topologically interesting patterns. The mesoscale morphology was projected onto a finite-element grid and the electrical conductivity of the films computed. The conductivity displayed non-monotonic behavior as a function of relative polymer fractions in the melt. Results are compared and contrasted with CNT dispersion in small-molecule fluids and mixtures.
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