NANO COMPOSITES

V. Gopi Krishna.

13MCD1053

Introduction

• The term "Nanotechnology" was invented byTaniguchi in 1974

• Nano science is the study of phenomena andmanipulation of materials at atomic, molecularand macromolecular scales, where propertiesdiffer significantly from those at a larger scale;while nanotechnology describesdesign, characterization, production andapplication of materials and systems bycontrolling the size at nanometer scale.

• A nanometer is so small that we cannot see

something of this size without the use of very

powerful microscopes. It is used to measure

things that are very tiny i.e. atoms and

molecules.

• Materials at this scale behave very differently

from when they are in larger form.

• This technology offers better built, long

lasting, cleaner, safer and smarter products for

the home, for medicine, for agriculture, for

communication and for industry in general.

Applications of Nano technology

Nano composites

• A nanocomposite is a matrix to whichnanoparticles have been added to improve aparticular property of the material less than100 nanometers (nm), or structures havingNano-scale repeat distances between thedifferent phases that make up the material.

• The properties of nanocomposite have causedresearchers and companies to consider usingthis material in several fields.

• In mechanical terms, nanocomposite differ

from conventional composite materials due to

the exceptionally high surface to volume ratio

of the reinforcing phase and/or its

exceptionally high aspect ratio.

• Nanocomposite are found in nature, for

example in the structure of the bone.

• Large amount of reinforcement surface areameans that a relatively small amount of nanoscalereinforcement can have an observable effect onthe macro scale properties of the composite.

• For example, adding carbon nanotubes improvesthe electrical and thermal conductivity.

• Other kinds of nanoparticulates may result inenhanced optical properties, dielectricproperties, heat resistance or mechanicalproperties such as stiffness, strength andresistance to wear and damage

Use and applications

• Producing batteries with greater power

output. Researchers have developed a method

to make anodes for lithium ion batteries from a

composite formed with silicon nanospheres

and carbon nanoparticles. The anodes made of

the silicon-carbon nanocomposite make closer

contact with the lithium electrolyte, which

allows faster charging or discharging of power.

Medical

• Speeding up the healing process for broken

bones. Researchers have shown that growth of

replacement bone is speeded up when a

nanotube - polymer nanocomposite is placed

as a kind of scaffold which guides growth of

replacement bone. The researchers are

conducting studies to better understand how

this nanocomposite increases bone growth.

• Producing structural components with a high

strength-to-weight ratio. For example an

epoxy containing carbon nanotubes can be

used to produce nanotube-polymer composite

windmill blades. This results in a strong but

lightweight blade, which makes longer

windmill blades practical. These longer blades

increase the amount of electricity generated by

each windmill.

• Using nanocomposite to make flexible

batteries. A nanocomposite of cellulous

materials and nanotubes could be used to make

a conductive paper. When this conductive

paper is soaked in an electrolyte, a flexible

battery is formed.

Gopi Krishna