New Insights Into Controlling Sub-Micron Failure Mechanisms in Composites Using Discrete Functionalized Multiwall Carbon Nanotubes

New technology has been developed that enables multiwall carbon nanotubes to be discrete, high aspect ratio and well bonded to the composite matrix of choice. Several composite types are examined using tubes of diameter about 12 nm and length about 700nm. Fully discrete, well-bonded tubes are shown to significantly enhance the matrix resistance to fracture and can be placed between fiber plies of composites. The challenges of maintaining the exfoliated state of discrete multiwall carbon nanotubes during composite part assembly from the liquid prepolymer to the cured part are discussed.

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Electrical self-sensing of impact damage in multiscale hierarchical composites with tailored location of carbon nanotube networks

Structural Health Monitoring ◽

10.1177/1475921718776198 ◽

2018 ◽

Vol 18 (3) ◽

pp. 806-818 ◽

Cited By ~ 4

Author(s):

BKS Isaac-Medina ◽

A Alonzo-García ◽

F Avilés

Keyword(s):

Carbon Nanotubes ◽

Finite Element Analysis ◽

Finite Element ◽

Electrical Resistance ◽

Impact Damage ◽

Multiwall Carbon Nanotubes ◽

Element Analysis ◽

The Matrix ◽

Hierarchical Composites ◽

Multiwall Carbon

Low-velocity impact damage in multiscale hierarchical composites comprising glass fiber weaves reinforcing a vinyl ester matrix with tailored location of multiwall carbon nanotubes is assessed through the changes of electrical resistance before and after impact. The location of the multiwall carbon nanotubes within the multiscale composite is controlled from manufacturing, rendering two hierarchical architectures. In the first one, as-received glass fiber weaves are used and the multiwall carbon nanotubes are only dispersed within the matrix, while in the second one the multiwall carbon nanotubes are dispersed within the matrix and also bonded to the glass fibers. Spatial electrical resistance maps are able to track the damage progression and growth of damage extension under consecutive impacts and the results are correlated to stresses determined by finite element analysis and ultrasonic C-scanning. The correlation between the electrical mapping and finite element analysis showed that the panels containing multiwall carbon nanotubes on the fiber are more sensitive to delamination and interfacial damage than the ones containing multiwall carbon nanotubes only dispersed within the polymer matrix.

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Effect of Matrix Viscosity on Rheological and Microwave Properties of Polymer Nanocomposites with Multiwall Carbon Nanotubes

Journal of Theoretical and Applied Mechanics ◽

10.2478/jtam-2014-0012 ◽

2014 ◽

Vol 44 (2) ◽

pp. 83-96 ◽

Cited By ~ 4

Author(s):

R. Kotsilkova ◽

E. Ivanov ◽

D. Bychanok ◽

A. Paddubskaya ◽

P. Kuzhir

Keyword(s):

Carbon Nanotubes ◽

Percolation Threshold ◽

Multiwall Carbon Nanotubes ◽

Electromagnetic Shielding ◽

Microwave Properties ◽

Multiwalled Carbon ◽

Low Viscosity ◽

The Matrix ◽

Multiwall Carbon ◽

Rheological Percolation

Abstract Nanocomposites of multiwalled carbon nanotubes (MWCNTs) in epoxy resin and polypropylene (PP) are studied. The effect of matrix viscosity on the degree of dispersion of nanotubes is determined by rheological methods. Rheology and microwave properties are correlated to estimate the optimal limits of nanofiller content required for improving the performance of nanocomposites. Rheological percolation threshold is determined for both types nanocomposites, ϕp=0.27% for the epoxy/MWCNT and; ϕp=1.5% for the PP/MWCNT, as found critical for achieving a network structure of interacting nanotubes in the matrix polymer. Good electromagnetic shielding efficiency was obtained for nanocomposites at nanotube contents above the rheological percolation. Low viscosity matrix facilitates contacts between MWCNTs, resulting in appearance of electromagnetic shielding at very low percolation threshold.

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Three-dimensional nanoprepreg and nanostitched aramid/phenolic multiwall carbon nanotubes composites: Experimental determination of in-plane shear

Journal of Composite Materials ◽

10.1177/0021998319854211 ◽

2019 ◽

Vol 53 (28-30) ◽

pp. 4077-4096 ◽

Cited By ~ 2

Author(s):

Kadir Bilisik ◽

Gulhan Erdogan ◽

Erdal Sapanci ◽

Sila Gungor

Keyword(s):

Carbon Nanotubes ◽

Three Dimensional ◽

Multiwall Carbon Nanotubes ◽

Nano Composites ◽

Plane Shear ◽

Pull Out ◽

Out Of Plane ◽

The Matrix ◽

Multiwall Carbon

In-plane shear of nanostitched three-dimensional para-aramid/phenolic composites were experimentally investigated. Adding the nanostitched fiber into nanoprepreg para-aramid fabric preform composites slightly improved their shear strengths. The carbon-stitched composite exhibited comparatively better performance compared to the para-aramid stitched composite probably due to well bonding between carbon fiber and phenolic resin. The stitched nano composites had mainly matrix breakages and micro shear hackles in the matrix; matrix debonding and filament pull-out in the composite interface; fibrillar peeling and stripping on the filaments due to angular deformation. This mechanism probably prohibited extensive interlaminar opening in the nanostitched composites. The result exhibited that the introducing of the nano stitched fiber where multiwall carbon nanotubes were transferred to the out-of-plane of the base structure enhanced its transverse fracture as a form of confined delamination area. Therefore, the damaged tolerance properties of the stitched nano composites were enhanced compared to the base.

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Boehmite Nanofibers as a Dispersant for Nanotubes in an Aqueous Sol

10.26434/chemrxiv.6652955.v1 ◽

2018 ◽

Author(s):

Gen Hayase

Keyword(s):

Carbon Nanotubes ◽

Aspect Ratio ◽

Aqueous Solutions ◽

High Aspect Ratio ◽

Multiwall Carbon Nanotubes ◽

Multiwall Carbon ◽

Nanotube Films

By exploiting the dispersibility and rigidity of boehmite nanofibers (BNFs) with a high aspect ratio of 4 nm in diameter and several micrometers in length, multiwall-carbon nanotubes (MWCNTs) were successfully dispersed in aqueous solutions. In these sols, the MWCNTs were dispersed at a ratio of about 5–8% relative to BNFs. Self-standing BNF–nanotube films were also obtained by filtering these dispersions and showing their functionality. These films can be expected to be applied to sensing materials.

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