Electrical conductivity of carbon-nanotube/cellulose composite paper

A functional carbon-nanotube (CNT)-composite paper is described in which the CNTs are aligned. This “aligned-CNT composite paper” is a flexible composite material that has CNT functionality (e.g., electrical conductivity) despite being a paper. An advanced fabrication method was developed to overcome the problem of previous CNT-composite papers, that is, reduced conductivity due to random CNT alignment. Aligning the CNTs by using an alternating current (AC) field was hypothesized to increase the electrical conductivity and give the paper an anisotropic characteristic. Experimental results showed that a nonionic surfactant was not suitable as a CNT dispersant for fabricating aligned-CNT composite paper and that catechin with its six-membered rings and hydrophilic groups was suitable. Observation by scanning electron microscopy of samples prepared using catechin showed that the CNTs were aligned in the direction of the AC field on the paper fibers. Measurement of the electric conductivity showed that the surface resistance was different between the direction of the aligned CNTs (high conductivity) and that of verticality (low). The conductivity of the aligned-CNT-composite paper samples was higher than that of nonaligned samples. This unique and functional paper, which has high and anisotropic conductivity, is applicable to a conductive material to control the direction of current.

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Multifunctional single-walled carbon nanotube–cellulose composite paper

Journal of Materials Chemistry ◽

10.1039/b924260k ◽

2010 ◽

Vol 20 (12) ◽

pp. 2400 ◽

Cited By ~ 66

Author(s):

Robin E. Anderson ◽

Jingwen Guan ◽

Michelle Ricard ◽

Girjesh Dubey ◽

Joseph Su ◽

...

Keyword(s):

Carbon Nanotube ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon ◽

Cellulose Composite ◽

Composite Paper

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Low-Frequency Noise in Carbon-Nanotube/Cellulose Composite Paper

Japanese Journal of Applied Physics ◽

10.1143/jjap.49.055101 ◽

2010 ◽

Vol 49 (5) ◽

pp. 055101

Author(s):

Tomo Tanaka ◽

Eiichi Sano ◽

Masanori Imai ◽

Kousuke Akiyama

Keyword(s):

Carbon Nanotube ◽

Low Frequency ◽

Frequency Noise ◽

Low Frequency Noise ◽

Cellulose Composite ◽

Composite Paper

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Fabrication and Characterization of Carbon Nanotube/Cellulose Composite Paper

Handbook of Polymer Nanocomposites. Processing, Performance and Application ◽

10.1007/978-3-642-45229-1_38 ◽

2015 ◽

pp. 195-211 ◽

Cited By ~ 1

Author(s):

Eiichi Sano ◽

Tomo Tanaka ◽

Masanori Imai

Keyword(s):

Carbon Nanotube ◽

Fabrication And Characterization ◽

Cellulose Composite ◽

Composite Paper

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Development of Paper Actuators Based on Carbon-Nanotube-Composite Paper

Molecules ◽

10.3390/molecules26051463 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1463

Author(s):

Takahiro Ampo ◽

Takahide Oya

Keyword(s):

Carbon Nanotubes ◽

Electrical Conductivity ◽

Carbon Nanotube ◽

Carbon Powder ◽

High Electrical Conductivity ◽

Soft Actuator ◽

Highly Efficient ◽

Semiconducting Properties ◽

Carbon Nanotube Composite ◽

Composite Paper

We propose a unique soft actuator—a paper actuator—based on carbon-nanotube-composite paper (CNT-composite paper), which is a composite of carbon nanotubes (CNTs) and paper. CNT-composite paper has highly efficient properties because of the contained CNTs, such as high electrical conductivity and semiconducting properties. We are considering using CNT-composite paper for various devices. In this study, we successfully developed a paper actuator. We determined the structure of the paper actuator by referencing that of bucky-gel actuators. The actuator operates using the force generated by the movement of ions. In addition to making the paper actuator, we also attempted to improve its performance, using pressure as an index and an electronic scale to measure the pressure. We investigated the optimal dispersant for use in paper actuators, expecting the residual dispersant on the CNT-composite paper to affect the performance differently depending on the type of dispersant. Referring to research on bucky-gel actuators, we also found that the addition of carbon powder to the electrode layers is effective in improving the pressure for paper actuators. We believe that the paper actuator could be used in various situations due to its ease of processing.

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Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites

Polymers ◽

10.3390/polym13091355 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1355

Author(s):

Astrid Diekmann ◽

Marvin C. V. Omelan ◽

Ulrich Giese

Keyword(s):

Electrical Conductivity ◽

Carbon Nanotube ◽

Mechanical Performance ◽

Softening Effect ◽

Electrical Percolation ◽

Optimum Parameters ◽

Lauryl Ether ◽

Solvent Residues ◽

Electrical Percolation Threshold ◽

Filler Dispersion

Incorporating nanofillers into elastomers leads to composites with an enormous potential regarding their properties. Unfortunately, nanofillers tend to form agglomerates inhibiting adequate filler dispersion. Therefore, different carbon nanotube (CNT) pretreatment methods were analyzed in this study to enhance the filler dispersion in polydimethylsiloxane (PDMS)/CNT-composites. By pre-dispersing CNTs in solvents an increase in electrical conductivity could be observed within the sequence of tetrahydrofuran (THF) > acetone > chloroform. Optimization of the pre-dispersion step results in an AC conductivity of 3.2 × 10−4 S/cm at 1 Hz and 0.5 wt.% of CNTs and the electrical percolation threshold is decreased to 0.1 wt.% of CNTs. Optimum parameters imply the use of an ultrasonic finger for 60 min in THF. However, solvent residues cause a softening effect deteriorating the mechanical performance of these composites. Concerning the pretreatment of CNTs by physical functionalization, the use of surfactants (sodium dodecylbenzenesulfonate (SDBS) and polyoxyethylene lauryl ether (“Brij35”)) leads to no improvement, neither in electrical conductivity nor in mechanical properties. Chemical functionalization enhances the compatibility of PDMS and CNT but damages the carbon nanotubes due to the oxidation process so that the improvement in conductivity and reinforcement is superimposed by the CNT damage even for mild oxidation conditions.

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Dual percolations of electrical conductivity and electromagnetic interference shielding in progressively agglomerated CNT/polymer nanocomposites

Mathematics and Mechanics of Solids ◽

10.1177/10812865211021460 ◽

2021 ◽

pp. 108128652110214

Author(s):

Xiaodong Xia ◽

George J. Weng

Keyword(s):

Experimental Data ◽

Electrical Conductivity ◽

Carbon Nanotube ◽

Percolation Threshold ◽

Polymer Nanocomposites ◽

Electromagnetic Interference ◽

Effective Medium Theory ◽

Scale Model ◽

Shielding Effectiveness ◽

Emi Shielding

Recent experiments have revealed two distinct percolation phenomena in carbon nanotube (CNT)/polymer nanocomposites: one is associated with the electrical conductivity and the other is with the electromagnetic interference (EMI) shielding. At present, however, no theories seem to exist that can simultaneously predict their percolation thresholds and the associated conductivity and EMI curves. In this work, we present an effective-medium theory with electrical and magnetic interface effects to calculate the overall conductivity of a generally agglomerated nanocomposite and invoke a solution to Maxwell’s equations to calculate the EMI shielding effectiveness. In this process, two complex quantities, the complex electrical conductivity and complex magnetic permeability, are adopted as the homogenization parameters, and a two-scale model with CNT-rich and CNT-poor regions is utilized to depict the progressive formation of CNT agglomeration. We demonstrated that there is indeed a clear existence of two separate percolative behaviors and showed that, consistent with the experimental data of poly-L-lactic acid (PLLA)/multi-walled carbon nanotube (MWCNT) nanocomposites, the electrical percolation threshold is lower than the EMI shielding percolation threshold. The predicted conductivity and EMI shielding curves are also in close agreement with experimental data. We further disclosed that the percolative behavior of EMI shielding in the overall CNT/polymer nanocomposite can be illustrated by the establishment of connective filler networks in the CNT-poor region. It is believed that the present research can provide directions for the design of CNT/polymer nanocomposites in the EMI shielding components.

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