Catalytically Grown Carbon Nanotubes of Small Diameter Have a High Young's Modulus

Effects of carbon nanotubes (CNT) addition on mechanical properties, electric conductivity and oxidation resistance of CNT/Al2O3-TiC composite were investigated. It was found that flexural strength, Young’s modulus and fracture toughness of the composites were improved by addition of more than 2 vol%-CNT. In the composites with more than 3 vol%-CNT, the oxidation resistance of the composite was degraded. In comparison with Al2O3-26vol%TiC sample as TiC particle-percolated sample, the Al2O3-12vol%TiC-3vol%CNT sample, which is not TiC particle-percolated sample, shows almost the same mechanical properties and electric conductivity, and also shows thinner oxidized region after oxidation at 1200°C due to less TiC in the composite.

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Modified rule of mixtures and Halpin–Tsai model for prediction of tensile strength of micron-sized reinforced composites and Young’s modulus of multiscale reinforced composites for direct extrusion fabrication

Advances in Mechanical Engineering ◽

10.1177/1687814018785286 ◽

2018 ◽

Vol 10 (7) ◽

pp. 168781401878528 ◽

Cited By ~ 8

Author(s):

Zirong Luo ◽

Xin Li ◽

Jianzhong Shang ◽

Hong Zhu ◽

Delei Fang

Keyword(s):

Carbon Nanotubes ◽

Tensile Strength ◽

Young’S Modulus ◽

Carbon Fibers ◽

Epoxy Resins ◽

Young's Modulus ◽

Resin Matrix ◽

Reinforced Composites ◽

Rule Of Mixtures ◽

Combined Use

A modified rule of mixtures is required to account for the experimentally observed nonlinear variation of tensile strength. A modified Halpin–Tsai model was presented to predict the Young’s modulus of multiscale reinforced composites with both micron-sized and nano-sized reinforcements. In the composites, both micron-sized fillers—carbon fibers—and nano-sized fillers—rubber nanoparticles and carbon nanotubes—are added into the epoxy resin matrix. Carbon fibers can help epoxy resins increase both the tensile strength and Young’s modulus, while rubber nanoparticles and carbon nanotubes can improve the toughness without sacrificing other properties. Mechanical experiments and scanning electron microscopy observations were used to study the effects of the micron-sized and nano-sized reinforcements and their combination on tensile and toughness properties of the composites. The results showed that the combined use of multiscale reinforcements had synergetic effects on both the strength and the toughness of the composites.

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On Young’s modulus of multi-walled carbon nanotubes

Bulletin of Materials Science ◽

10.1007/s12034-008-0032-2 ◽

2008 ◽

Vol 31 (2) ◽

pp. 185-187 ◽

Cited By ~ 32

Author(s):

K. T. Kashyap ◽

R. G. Patil

Keyword(s):

Carbon Nanotubes ◽

Young’S Modulus ◽

Young's Modulus ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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The Structure and the Mechanical Properties of a Newly Fabricated Cellulose-Nanofiber/Polyvinyl-Alcohol Composite

MRS Proceedings ◽

10.1557/opl.2014.141 ◽

2014 ◽

Vol 1621 ◽

pp. 149-154

Author(s):

Yukako Oishi ◽

Atsushi Hotta

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Young’S Modulus ◽

Young's Modulus ◽

Cellulose Nanofibers ◽

Small Diameter ◽

Short Fiber ◽

Cellulose Nanofiber ◽

Process Conditions ◽

Aspect Ratios

ABSTRACTCellulose nanofibers (Cel-F) were extracted by a simple and harmless Star Burst (SB) method, which produced aqueous cellulose-nanofiber solution just by running original cellulose beads under a high pressure of water in the synthetic SB chamber. By optimizing the SB process conditions, the cellulose nanofibers with high aspect ratios and the small diameter of ∼23 nm were obtained, which was confirmed by transmission electron microscopy (TEM). From the structural analysis of the Cel-F/PVA composite by the scanning electron microscopy (SEM), it was found that the Cel-F were homogeneously dispersed in the PVA matrix. Considering the high molecular compatibility of the cellulose and PVA due to the hydrogen bonding, a good adhesive interface could be expected for the Cel-F and the PVA matrix. The influences of the morphological change in Cel-F on the mechanical properties of the composites were analysed. The Young’s modulus rapidly increased from 2.2 GPa to 2.9 GPa up to 40 SB treatments (represented by the unit Pass), whereas the Young’s modulus remained virtually constant above 40 Pass. Due to the uniform dispersibility of the Cel-F, the Young’s modulus of the 100 Pass composite at the concentration of 5 wt% increased up to 3.2 GPa. The experimental results corresponded well with the general theory of the composites with dispersed short-fiber fillers, which clearly indicated that the potential of the cellulose nanofibers as reinforcement materials for hydrophilic polymers was sufficiently confirmed.

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Effective reinforcements for thermoplastics based on carbon nanotubes of oil fly ash

Scientific Reports ◽

10.1038/s41598-019-56777-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Numan Salah ◽

Abdulrahman Muhammad Alfawzan ◽

Abdu Saeed ◽

Ahmed Alshahrie ◽

Waleed Allafi

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Tensile Strength ◽

Fly Ash ◽

Young’S Modulus ◽

Raw Materials ◽

Young's Modulus ◽

Weight Fraction ◽

Low Weight ◽

Oil Fly Ash

AbstractCarbon nanotubes (CNTs) are widely investigated for preparing polymer nanocomposites, owing to their unique mechanical properties. However, dispersing CNTs uniformly in a polymer matrix and controlling their entanglement/agglomeration are still big technical challenges to be overcome. The costs of their raw materials and production are also still high. In this work, we propose the use of CNTs grown on oil fly ash to solve these issues. The CNTs of oil fly ash were evaluated as reinforcing materials for some common thermoplastics. High-density polyethylene (HDPE) was mainly reinforced with various weight fractions of CNTs. Xylene was used as a solvent to dissolve HDPE and to uniformly disperse the CNTs. Significantly enhanced mechanical properties of HDPE reinforced at a low weight fraction of these CNTs (1–2 wt.%), mainly the tensile strength, Young’s modulus, stiffness, and hardness, were observed. The tensile strength and Young’s modulus were enhanced by ~20 and 38%, respectively. Moreover, the nanoindentation results were found to be in support to these findings. Polycarbonate, polypropylene, and polystyrene were also preliminarily evaluated after reinforcement with 1 wt.% CNTs. The tensile strength and Young’s Modulus were increased after reinforcement with CNTs. These results demonstrate that the CNTs of the solid waste, oil fly ash, might serve as an appropriate reinforcing material for different thermoplastics polymers.

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Simulation of Young's modulus of single-walled carbon nanotubes by molecular dynamics

Physica B Condensed Matter ◽

10.1016/j.physb.2004.07.005 ◽

2004 ◽

Vol 352 (1-4) ◽

pp. 156-163 ◽

Cited By ~ 160

Author(s):

Bao WenXing ◽

Zhu ChangChun ◽

Cui WanZhao

Keyword(s):

Carbon Nanotubes ◽

Molecular Dynamics ◽

Young’S Modulus ◽

Young's Modulus ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Walled Carbon Nanotubes

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Fabrication and Testing of Planar Stent Mesh Designs Using Carbon-Infiltrated Carbon Nanotubes

Journal of Nanotechnology in Engineering and Medicine ◽

10.1115/1.4025598 ◽

2013 ◽

Vol 4 (2) ◽

Cited By ~ 6

Author(s):

Kristopher Jones ◽

Brian D. Jensen ◽

Anton Bowden

Keyword(s):

Carbon Nanotubes ◽

Young’S Modulus ◽

Fracture Strain ◽

Young's Modulus ◽

Chemical Vapor ◽

Pyrolytic Carbon ◽

Compression Tests ◽

Element Analysis ◽

Percent Elongation ◽

Fea Model

This paper explores and demonstrates the potential of using pyrolytic carbon as a material for coronary stents. Stents are commonly fabricated from metal, which has worse biocompatibilty than many polymers and ceramics. Pyrolytic carbon, a ceramic, is currently used in medical implant devices due to its preferable biocompatibility properties. Micropatterned pyrolytic carbon implants can be created by growing carbon nanotubes (CNTs), and then filling the space between with amorphous carbon via chemical vapor deposition (CVD). We prepared multiple samples of two different stent-like flexible mesh designs and smaller cubic structures out of carbon-infiltrated carbon nanotubes (CI-CNT). Tension loads were applied to expand the mesh samples and we recorded the forces at brittle failure. The cubic structures were used for separate compression tests. These data were then used in conjunction with a nonlinear finite element analysis (FEA) model of the stent geometry to determine Young's modulus and maximum fracture strain in tension and compression for each sample. Additionally, images were recorded of the mesh samples before, during, and at failure. These images were used to measure an overall percent elongation for each sample. The highest fracture strain observed was 1.4% and Young's modulus values confirmed that the material was similar to that used in previous carbon-infiltrated carbon nanotube work. The average percent elongation was 86% with a maximum of 145%. This exceeds a typical target of 66%. The material properties found from compression testing show less stiffness than the mesh samples; however, specimen evaluation reveals poorly infiltrated samples.

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