Interfacial fracture energy measurements for multi-walled carbon nanotubes pulled from a polymer matrix

2004 ◽  
Vol 64 (15) ◽  
pp. 2283-2289 ◽  
Author(s):  
Asa H. Barber ◽  
Sidney R. Cohen ◽  
Shmuel Kenig ◽  
H.Daniel Wagner
Keyword(s):  
Carbon Nanotubes ◽  
Fracture Energy ◽  
Polymer Matrix ◽  
Interfacial Fracture ◽  
Multi Walled Carbon Nanotubes ◽  
Interfacial Fracture Energy ◽  
Walled Carbon Nanotubes

Effect of nanofiller on fibre laser drilling quality of carbon fibre reinforced polymer composite laminates

2018 ◽  
Vol 233 (4) ◽  
pp. 857-870
Author(s):  
Dhiraj Kumar ◽  
Kalyan Kumar Singh
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Fibre ◽  
Polymer Matrix ◽  
Composite Laminates ◽  
Reinforced Polymer ◽  
Carbon Fibre Reinforced Polymer ◽  
Multi Walled Carbon Nanotubes ◽  
Fibre Reinforced Polymer ◽  
Walled Carbon Nanotubes

Laser machining of carbon fibre reinforced polymer composites is a challenging task due to a significant difference between physical and thermal properties of the constituent materials, i.e. polymer matrix and carbon fibres. This results in extended heat-affected zone (HAZ), taper kerf and poor surface finishing. This paper focuses on an investigation, attempting to minimise the divergence in the decomposition temperature of carbon fibres and epoxy resin by adding multi-walled carbon nanotubes in polymer matrix as a secondary reinforcement. High thermal conductivity of multi-walled carbon nanotubes increases the thermal diffusivity of polymer matrix, which in turn reduces the matrix recession. In addition, laser power and scan speed was also considered as an input parameter and their influence on output responses such as HAZ, taper angle and surface roughness has been studied. To analyse the effect of multi-walled carbon nanotubes on the resultant thermal damage, an innovative technique, i.e. scanning acoustic microscopy was used. This technique provides a ply-by-ply damage analysis. C-scans of the top and bottom surface of the machined holes in the composite were also carried out. Further, micrographs of the holes were taken to analyse the quality of the holes using field-emission scanning electron microscope. The obtained results indicated that HAZ, taper angle and surface roughness of holes decreased by ∼30%, ∼47% and ∼43%, respectively, with 1.5 wt% multi-walled carbon nanotubes doped carbon fibre reinforced polymer laminates, when compared with the results obtained from experiments with neat carbon fibre reinforced polymer composite laminates.

Mechanically Compliant Electrodes and Dielectric Elastomers from PEG-PDMS Copolymers

MRS Advances ◽  
2016 ◽  
Vol 1 (52) ◽  
pp. 3497-3508
Author(s):  
Aliff Hisyam A Razak ◽  
Frederikke Bahrt Madsen ◽  
Anne Ladegaard Skov
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Molecular Weight ◽  
Polymer Matrix ◽  
High Conductivity ◽  
Stress And Strain ◽  
Multi Walled Carbon Nanotubes ◽  
Highly Stretchable ◽  
Walled Carbon Nanotubes ◽  
Compliant Electrodes

ABSTRACTSoft conducting elastomers have been prepared from polydimethylsiloxane-polyethyleneglycol (PDMS-PEG) copolymer and surfactant-stabilized multi-walled carbon nanotubes (MWCNTs). The copolymer was chain-extended with PDMS of molecular weight 17.2 kg mol-1 in order to obtain a crosslinkable PDMS with molecular weight around 20 – 30 kg mol-1. MWCNTs were treated with surfactant and sonicated for better dispersion in the polymer matrix. The conductivity and mechanical properties of conducting elastomers were thoroughly investigated including stress and strain at break. The developed conducting elastomers showed high conductivity combined with inherent softness. The high conductivity and softness, PDMS-PEG copolymers with incorporated MWCNTs hold great promises as compliant and highly stretchable electrodes for stretchable devices such as electro-mechanical transducers.

Micro-mechanical failure prediction of radar-absorbing structure dispersed with multi-walled carbon nanotubes considering multi-scale modeling

2017 ◽  
Vol 52 (12) ◽  
pp. 1649-1660 ◽  
Author(s):  
Young-Woo Nam ◽  
Jae-Hwan Shin ◽  
Jae-Hun Choi ◽  
Hyun-Seok Kwon ◽  
Jae-Sung Shin ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Polymer Matrix ◽  
Volume Element ◽  
Mechanical Failure ◽  
Multi Scale ◽  
Scale Modeling ◽  
Multi Walled Carbon Nanotubes ◽  
Multi Scale Modeling ◽  
Radar Absorbing Structure ◽  
Walled Carbon Nanotubes

Conventional radar-absorbing structure is typically manufactured with high weight percentage (wt.%) of carbonaceous nano-conductive particles in the polymer matrix to tailor its microwave absorbing performance. However, these manufacturing methods have some physical limitations with regard to fabrication, due to the high viscosity in the polymer matrix and, inhomogeneous in mechanical and electrical properties. No study has been conducted with micro-mechanical failure prediction of radar-absorbing structure dispersed with multi-walled carbon nanotubes. In order to address these limitations, radar-absorbing structures dispersed with multi-walled carbon nanotubes were designed in the Ku-band (12.4–18 GHz). Additionally, to establish and verify the micro-mechanical failure analysis based on multiscale modeling, finite element analysis was carried out using the Mori–Tanaks mean-field homogenization model within the representative volume element model in the microstructure. In order to verify the Hashin criteria of radar-absorbing structure dispersed with multi-walled carbon nanotube (0.5 wt.%, 1.0 wt.% and 1.5 wt.%), mechanical tests (tensile, compressive and shear test) were conducted according to ASTM standards. In this paper, radar-absorbing structure with irregularly arranged filler and matrix with representative volume element was modeled from the micro-mechanical point of view and the results from Hashin failure criterion were verified both by simulations and experimental results of prediction strengths within the expected error range (lower than 6%). The reliability of application in micro-mechanical prediction of radar-absorbing structure was confirmed considering the multi-scale modeling.

Improving the mechanical properties of Fe3O4/carbon nanotube reinforced nanocomposites by a low-magnetic-field induced alignment

2018 ◽  
Vol 38 (8) ◽  
pp. 731-738
Author(s):  
Yifan Huang ◽  
Weicheng Jiao ◽  
Yue Niu ◽  
Guomin Ding ◽  
Rongguo Wang
Keyword(s):  
Magnetic Field ◽  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Field Strength ◽  
Polymer Matrix ◽  
Inert Gas ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Low Magnetic Field

Abstract The aim of the paper is to develop a novel nanocomposite with high mechanical properties. The mechanical properties are improved by aligning the Fe3O4/multi-walled carbon nanotubes (MWCNTs) into a highly oriented manner in epoxy resin (EP) via a low magnetic field. Fe3O4 nanoparticles were tethered onto the surface of MWCNTs by a novel water-in-oil (W/O) method without heating at high temperatures or the protection of inert gas. Then, the modified magnetic MWCNTs (m-MWCNTs) were added into EP and aligned in a low magnetic field (100 mT). A method was presented to estimate the minimum magnetic field strength for aligning the m-MWCNTs. Besides, the morphology and microstructures of the fabricated m-MWCNTs and m-MWCNTs/EP highly ordered nanocomposites were characterized. Finally, the mechanical properties measurements were performed. The results of the experiments showed that this method was very efficient in aligning m-MWCNTs embedded in polymer matrix leading to a highly ordered composite for improving mechanical properties.

scholarly journals Thermal and Structural Properties of High Density Polyethylene/Carbon Nanotube Nanocomposites: A Comparison Study

Chemosensors ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 136
Author(s):  
Ayat Bozeya ◽  
Yahia F. Makableh ◽  
Rund Abu-Zurayk ◽  
Aya Khalaf ◽  
Abeer Al Bawab
Keyword(s):  
Carbon Nanotubes ◽  
Polymer Matrix ◽  
High Density Polyethylene ◽  
High Density ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Melt Compounding ◽  
Multi Walled Carbon Nanotubes ◽  
Functionalization Of Carbon Nanotubes ◽  
Walled Carbon Nanotubes

The effects of functionalization of carbon nanotubes on the properties of nanocomposite sheets prepared from high-density polyethylene (HDPE) and carbon nanotubes (CNTs) were investigated. Carbon nanotubes were first oxidized, followed by amine group functionalization. The Fourier transform-infrared (FTIR) spectroscopy results confirm the presence of oxygenated and amide groups at the surface of the CNTs after each treatment. The HDPE/CNT nanocomposites sheets were prepared using a melt compounding method. Six types of CNTs were used; pristine Single-walled Carbon nanotubes (SWCNT) and pristine Multi-walled Carbon nanotubes (MWCNT), oxidized (O-SWCNT and O-MWCNT) and amide (Amide-SWCNT and Amide-MWCNT). All prepared nanocomposite sheets were characterized using Thermal gravimetric analysis (TGA), Differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electronic microscope (SEM). TGA results measured increased thermal stability of the polymer with the addition of CNTs, O-MWCNT showed the best enhancement. XRD measurements confirmed that the addition of CNTs did not change the crystal structure of the polymer, although the crystallinity was decreased. The maximum crystallinity decrease resulted from O-SWNTs addition to the polymer matrix. SEM imaging showed that oxidized and functionalized CNTs have more even dispersion in the polymer matrix compared with pristine CNTs.

Significantly enhanced dielectric response in composite of P(VDF-TrFE) and modified multi-walled carbon-nanotubes

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Jingwen Wang ◽  
Nan Wei ◽  
Fang Wang ◽  
Congcong Wu ◽  
Shuqin Li
Keyword(s):  
Carbon Nanotubes ◽  
Dielectric Constant ◽  
Percolation Threshold ◽  
Polymer Matrix ◽  
Vinylidene Fluoride ◽  
Volume Fraction ◽  
Poly Vinylidene Fluoride ◽  
Multi Walled Carbon Nanotubes ◽  
High Dielectric ◽  
Walled Carbon Nanotubes

AbstractTo develop a high dielectric constant composite of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] and multi-walled carbon-nanotubes (MWCNTs) with desirable homogeneity, MWCNTs were treated with a nitro-sulfuric acid by ultrasonication. Improvement of the dispersibility of chemically modified MWCNTs (a-MWCNTs) in polymer matrix, in comparison with that of unmodified MWCNTs in P(VDF-TrFE), was confirmed by field emission scanning electron microscopy (FESEM)-observed morphologies. Electric behavior of the composites with different volume fraction of dispersed carbon nanotubes phase can be described mainly by percolation theory. The percolation threshold (fc) of composites with a-MWCNTs (fc=0.0308) is larger than that of composites with MWCNTs (fc=0.0216) due to better dispersion of a-MWCNTs in polymer matrix and the reduction of aspect ratio of a-MWCNTs occurred in the modification procedure. The composite with 2.98 vol% (a volume fraction close to the percolation threshold) of a-MWCNTs has a dielectric constant of 592 at 100Hz and room temperature. The composite remains very flexible with an elastic modulus close to that of the parent copolymer.

scholarly journals Mode II Interfacial Fracture Toughness of Multi-Walled Carbon Nanotubes Reinforced Nanocomposite Film on Aluminum Substrate

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 904
Author(s):  
Shiuh-Chuan Her ◽  
Pao-Chu Chien
Keyword(s):  
Carbon Nanotubes ◽  
Fracture Toughness ◽  
Elastic Modulus ◽  
Fracture Energy ◽  
Composite Structure ◽  
Nanocomposite Film ◽  
Mode Ii ◽  
Interfacial Fracture Toughness ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

In this investigation, various loadings of multi-walled carbon nanotubes (MWCNTs) ranging from 0.3–1.0 wt % were incorporated into the epoxy to fabricate the nanocomposites. Nanocomposite film with a thickness of 0.2 mm was deposited on an aluminum substrate through a hot-pressing process. Theoretical expression of the model II strain energy release rate for the film/substrate composite structure was derived. End-notched flexure (ENF) tests were performed to characterize the mode II fracture energy of the composite structure. Experimental results indicate that the elastic modulus, ultimate strength, and mode II fracture energy increase as the MWCNT loading in the nanocomposite increases. In the case of nanocomposite film with 1.0 wt % of MWCNTs, the elastic modulus, ultimate strength, and mode II interfacial fracture toughness are increased by 20.6%, 21.1%, and 54.4%, respectively in comparison with neat epoxy. In addition, the dispersion of MWCNTs in the epoxy-based matrix was investigated using scanning electron microscope (SEM). The SEM images depict that MWCNTs are well dispersed leading to the enhancement of the mechanical properties of the nanocomposite.

Sign in / Sign up

Export Citation Format

Share Document