Flavin Mononucleotide-Mediated Formation of Highly Electrically Conductive Hierarchical Monoclinic Multiwalled Carbon Nanotube-Polyamide 6 Nanocomposites

Abstract

Although the multiwalled carbon nanotube (MWNT) is a promising material for use in the production of high electrical conductivity (σ) polymer nanocomposites, its tendency to aggregate and distribute randomly in a polymer matrix is a problematic issue. In the current study, we developed a highly conductive and monoclinically aligned MWNT-polyamide 6 (PA) nanocomposite containing interfacing flavin moieties. In this system, the flavin mononucleotide (FMN) initially serves as a noncovalent aqueous surfactant for individualizing MWNTs in the form of FMN-wrapped MWNTs (FMN-MWNT), and then partially decomposed FMN (dFMN) induces crystallization of the PA on the MWNTs. The results of experiments performed using material subjected to partial dissolution of PA matrix show that the nanocomposite PA-dFMN-MWNT, formed by melt extrusion of PA and dFMN-MWNT, contains a three-dimensional monoclinic MWNT network embedded in an equally monoclinic PA matrix. An increase in monoclinic network promoted by an increase in the content of MWNT increases σ of the nanocomposite up to 100 S/m, the highest value reported for a polymer-MWNT nanocomposite. X-ray diffraction along with transmission electron microscopy reveal that the presence of dFMN induces the formation of monoclinic PA on dFMN-MWNT. The high σ of the PA-dFMN-MWNT nanocomposite is also a consequence of a minimization of defect formation of MWNT by noncovalent functionalization. Hierarchical structural ordering, yet individualization of MWNTs, provides a viable strategy to improve the physical property of nanocomposites.

Preparation of high‐performance carbon nanotube/polyamide composite materials by elastic high‐shear kneading and improvement of properties by induction heating treatment

“…Since CNT has excellent mechanical properties, it is attracting attention as a filler for reinforcing polymer materials, and is also highly expected to be used as a conductivity‐imparting material. Cao et al report in detail on the conductive mechanism of CNTs, 42 and many other researchers have contributed detailed reports on this topic 43–52 . The most common application to be developed is the use of CNTs for electromagnetic wave shielding; polymer matrix composite materials 43–48 are also attracting attention for their effects on electromagnetic wave shielding.…”

“…Cao et al report in detail on the conductive mechanism of CNTs, 42 and many other researchers have contributed detailed reports on this topic 43–52 . The most common application to be developed is the use of CNTs for electromagnetic wave shielding; polymer matrix composite materials 43–48 are also attracting attention for their effects on electromagnetic wave shielding. As seen in the development of flexible materials, 43 flexible materials have a very wide range of uses, including application to various sensors, flexible electrodes, flexible devices, and wearable systems 52 .…”

“…Cao et al report in detail on the conductive mechanism of CNTs, 42 and many other researchers have contributed detailed reports on this topic. [43][44][45][46][47][48][49][50][51][52] The most common application to be developed is the use of CNTs for electromagnetic wave shielding; polymer matrix composite materials [43][44][45][46][47][48] are also attracting attention for their effects on electromagnetic wave shielding. As seen in the development of flexible…”

Carbon Nanotube/Polymer Coaxial Cables with Strong Interface for Damping Composites and Stretchable Conductors

“…This conductivity is higher than most reported CNT/polymer composites even with more CNT content (Figure 6a). [33][34][35][36][37] Upon being stretched to a strain of 100% or bent into an angle of 180°, the composite resistance ratio (R/R 0 , where R and R 0 is resistance at stretched and original state, respectively) of the SWNT@MWNT/PDMS cable is 1.07 and 1.02, respectively (Figure 6b,c). After recovering to the original state, the resistance changes are only 0.19% and 0.03%, respectively.…”

Deterministic transfer of thin carbon nanotube film

“…Next, the electrical contact between SWNT film and electrodes was addressed. Resistivity of SWNT films were measured by two probe method 12 . For this, carbonaceous impurity (CI) which is graphitic nanoparticle was intentionally added to modulate electrical resistivity.…”