Cnt Composite Fibers

8/9/2019 Cnt Composite Fibers

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CarbonCarbon NanotubeNanotube

CompositeComposite FibresFibres

Presented By:

Shashank OstaVikas choudhary


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The Future Beckons:

CNT Composites

Most exciting area

Huge potential

Application of Carbon Nanotubes : modify

properties of other materials.


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Exceptional Properties - Mechanical, Electrical andThermal imparted to the composites.

Possess one of the highest known thermal conductivity

Mixing nanotube dispersions with solutions of thepolymer Or incorporating it in polymer matrices.

Some Examples Include: Nanotube/PVA composite Nanotube/polystyrene composites (melt spinning)

Carbon Nanotube/Polyacrylonitrile CompositeFiber Nanotube-Nylon Composite Fiber


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But Lifes not that easy:

The Challenges Faced The small size scale of the CNTs which presents

serious processing challenges.

High cost of carbon nanotubes.

The purification of CNTs Impurities such as graphite sheets, amorphous carbon, metal

catalyst and the smaller fullerenes etc. propose challenges.

SWNT samples have to be homogeneous.


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Some more

Insufficient bonding at the nanotubes/matrixinterface due to interface fracture

The difficulty of aligning the tubes within the matrix

Solvents used influence the mechanicalperformance of the composite

CNTs in the matrix tend to stick together,


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High quality/high purity carbon nanotubes currentlycost $800/g and even ones with defects and impurities(metal catalyst and amorphous carbon) cost $535/g

The scale-up limitations of arc discharge and laserablation make the cost of nanotubes-basedcomposites prohibitive

And More


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Lets Purify The CNTs:

The Purification Techniques Oxidation

Oxidative treatment of the SWNTs to remove carbonaceous impurities or toclear the metal surface

Acid treatment

Metal catalyst exposed to acid and solvated

AnnealingNanotubes will be rearranged and defects will be consumed at hightemperatures (873 1873 K)


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Ultrasonication

Agglomerates of different nanoparticles forced to vibrate and

will become more dispersed.

Magnetic Purification

Ferromagnetic (catalytic) particles are mechanically removed from their

graphitic shells

Micro filtration

Based on size or particle separation


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Cutting Chemically

Mechanically

Combination

Functionalisation

Making SWNTs more soluble than the impurities by attaching other groupsto the tubes

ChromatographySeparate small quantities of SWNTs into fractions with small length and

diameter distribution


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SEM Characterization at Different Stages Of

purification

Images of (a) c-SWNT, (b) residue from 1600g, (c) residue from 16000g,(d) supernatant from 16000g, (e) residue from 325000g, and (f) supernatant from 325000g.


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Single Wall Carbon Nanotube/Polyacrylonitrile

Composite Fiber

PAN synthesized using free radical polymerization

Wet spinning used to produce fibers

Dissolved in N, N-Dimethyl Formamide (DMF)

The Making Of

CNT Composites


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SWNT/PAN Fiber Spinning


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Single-Walled Carbon Nanotube-NylonComposite Fiber


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Fabrication of Nylon composite fiber

Heated at 250 C for 20 min

Spinneret pressurized with nitrogen (50 psi)

Extruded from hole of dia 400 microns

Cooled in the ambient atmosphere


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Figure. (a) Schematic of the fiber spinneret setup.(b) Photograph of the spinneret setup. (c) Photograph of the composite fiber.(d) SEM image of cross-sectional fracture of the composite fiber.


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Aromatic Polyamide CNT Composites

Composite comprising SWNTand AromaticPolyamide made by :-

Suspending SWNT in an acid to form a nanotube-acid mixture

Adding Aromatic Amide

Dispersing the single-wall carbon nanotubes in the polyamide to

form a SWNT-Polyamide dope

The dope can be spun into a fiber or formedinto a film

Preferred polyamide is poly(p-phenylene terephthalamide)


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Properties

Electrical properties

Nanotubes have been used as an alternative to carbon black.

Used to increase the conductivity of relatively low cost polymers

Optical properties Have electroluminescent properties, and are widely used in light-emitting

diodes

Mechanical properties Incorporation of SWNTs into polymer matrix increases the tensile

strength and Youngs modulus


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Electrostatic Applications

In Aircraft ComponentsEnhanced Electrical conductivity provide electrostatic discharge andelectromagnetic radio frequency interference protection

Computer housings and exterior automotiveparts

Printable conductors for organic electronicsdevices


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Optoelectronic Applications

Composite used as the emissive layer in anorganic light-emitting diode (LED)

Photovoltaic devices


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Electronic Textile applications

Distributed Sensors

Electronic Interconnects Electromagnetic Shielding

Antennas

Batteries

Electronic textile applications promising for Composite Carbon Nanotube fibers,which are easily woven or sewn into textiles are:-


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High Strength Applications

Structural Composites

Ballistic Protection Applications

Armor for personnel, structures and vehicles


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References

The Wondrous World of Carbon Nanotubes(a review of current

carbon nanotube technologies) Eindhoven University ofTechnology

Continuous carbon nanotube composite fibers: properties,potential

applications, and problems( Alan B. Dalton,*a Steve Collins,a Joselito

Razal,a Edgar, Munoz,a Von Howard Ebron, Bog G. Kim,a

Jonathan N. Coleman,b John P. Ferrarisa and Ray H. Baughmana )

Carbon nanotube composites (P. J. F. Harris*)

Single Wall Carbon Nanotube/Polyacrylonitrile Composite Fiber(By

Jianghong Liang) Georgia Institute ofTechnology October, 2004

Continuous Spinning of a Single-Walled Carbon Nanotube-Nylon

Composite Fiber(Junbo Gao, Mikhail E. Itkis,, Aiping Yu, Elena

Bekyarova, Bin Zhao, and Robert C. Haddon) September 5, 2004 Carbon nanotube reinforced composites: Potential and current

challenges Amal M.K. Esawi , a, and Mahmoud M. Faraga, (25

September 2006)


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Thank You

Have Fun!

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Cnt Composite Fibers