Bahir Dar University

EiTEX

Nano-Technology application in Textiles

By: Bademaw Abate

Nanotechnology The design, characterization, production and application of

structures, devices and systems by controlling shape and size of

building blocks at the nanometer scale.

The study of control of matter on an atomic and molecular scale.

Involves engineering on a small scale to create smaller, cheaper,

lighter, and faster devices that can do more things with less raw

materials.

How small is Nano

Units in nanometers (nm) : 1nm= 10-9m

3 types of nanotechnology in textiles can be distinguished:

Nanotechnology in fibres and yarns (fabrics)

Nanotechnology in coatings (textile finishing)

E-textiles

What is a Nanofiber?A nanofiber is a continuous fiber which has a

diameter in the range of billionths of a meter.

The smallest Nano fibers made today are between 1.5 and 1.75 nanometers

Cont..

Nanoscale materials can be rationally designed to exhibit novel and significantly improved physical, chemical and biological properties, because of their size.

Nonwoven fabrics composed of electro spun nanofibres have :a large specific surface area,

a high porosity

a small pore size in comparison with commercial textiles making them excellent candidates for use in filtration, medical and membrane applications.

Nano particleProperties

Dramatic change in properties of a substance when

particle size reduced to nanometer range

Normal ceramic particle Brittle

Nano ceramic particle Deformable, flexible

Normal Gold Yellow

Nano gold Red

Nanotechnology has real commercial potential for thetextile industry. Why?

conventional methods used to impart different properties to fabrics

will lose their functions after several laundering or wearing. Reduce breathability

Comfort

Nanotechnology can provide high durability for fabricsbecause: nano-particles have a large surface area-to-volume ratio

high surface energy.

Coating of nano-particles on fabrics will not affect theirbreathability or hand feel.

Different structures of Nano Particles…

Whiskers

Fiber

Spine

Hooks

Whiskers

Fiber

The whiskers get hooked on the fibers to alter the fabric property.

Nano Whiskers can make the fabric stain & water resistant…

Nano whiskers can keep the fabric breathable too unlike resins finishes!

Value addition due to Nano Whiskers…

Water and oil repellency

Superior durability

Breathable

Fabric remains soft, natural

Wrinkle resistance

Net

Three Dimensional Molecular Nano Net covers the core fiber Completely.

Value addition due to Nano Net…

• Alters the property of synthetic fibers like Polyester to give a feel of cotton & linen.

• Wicks body moisture fast

• Dries quickly & gives the cooling effect.

Wrap

Nano sheet wraps the fiber completely to cover it & alter its property.

Nano wraps can enhance the fabric Wash

fastness…

Normal fabric trouser with out nano wrap on the fibers after 50 washes!

Trouser made up fabric with nano wrap fibers after 50 washes!

Value addition due to Nano Wrap

Strength and Durability

Improvement in colorfastness

Crease Retention

Static Resistance

Some Magic Nano Particles…

Clay Nano Particles

ZnO Nano Particles

TiO2 Nano Particles

MgO Nano Particles

Silver Nano Particles

Textile Applications of Nano Technology...

FUNCTIONALwater repellent

PROTECTIONUV absorption

DURABILITYcolor fastness

DURABILITYabrasion

SAFETYfire retardancy

FUNCTIONAL HYGIENEAnti-microbial

FUNCTIONAL PROTECTIONControlled release

of additives

Nano TreatedTextile

FUNCTIONAL PROTECTIONself-cleaning

Integration of nanoparticles in textiles

Nanoparticles can be introduced in the textile

production process at two levels :

during the melt extrusion of yarns nanoparticles based on clay, metal oxides or carbon nanotubes (CNTs) can be

mixed in the polymer before the extrusion step.

This allows new functionalities to be incorporated

during the coating.

Application

The fabric is padded and dried.

During drying water evaporates.

During subsequent curing operation the polymers melt and spread giving uniform coating of fibresdue to nano size of the finishing agent.

Antibacterial and Deodorant finishes based on nanotechnology

'Ag fresh' Typical example: when human body perspire the

clothing in contact with skin such as socks, shirts etcsmell due to growth of bacteria.

This drawback is eliminated by Ag fresh finish

incorporate silver particles in a size of around 4nm into fiber

A material of superior antibacterial, deodorant properties with good laundering fastness has been brought about by letting silver particles penetrate into the fiber itself.

Ag nanoparticle penetration in fibre

The metal ions catalyze the production of oxygen radicals that oxidize molecular

structure of bacteria.

'Ag fresh'

The 'Ag fresh' antibacterial, deodorant finish has been developed for use mainly in

garments worn close to the skin,

Further applications of this technology are being planned for use in uniforms, casual wear, shirts, bedding, nightwear, underwear, polo shirts.

Self cleaning clothes Titanium dioxide nanoparticles are catalysts that help break down carbon-

based molecules,

Require only sunlight to trigger the reaction

The inventors believe that these fabrics could be made into self-cleaning clothes that tackle dirt, environmental pollutants and harmful microorganisms

The titanium dioxide particles covering the fibres are 20 nm size

Water Repellent and Self Cleaning Hydrophobic finishes lower the surface energy and can give a

maximum water contact angle of roughly 120 degree.

To get higher contact angle and to have the self-cleaning ability,

Surfaces with contact angle between 150 to 180 degree are required

.

SiO2, Al2O3 nanoparticles

are mainly used for super

water repellent finishes.

E-Textiles Smart/interactive textiles (SIT) are materials and structures that sense and react

to environmental conditions or stimuli, such as those from mechanical, thermal,

chemical, electrical, magnetic or other sources.

Trigger or

Stimuli

Response

or Action

CO

NT

RO

LL

ING

The sensors provide a nerve

system to detect signals

The processor analyzes and

evaluates the signals

The actuators act upon the detected

and evaluated signal either directly or

from a central control unit

Applications of Nanotechnology In Military

Science:

Military uniforms that change color to match the environment

Light weight bullet-proof vests

Applications of Nanotechnology

• Stain/odor-free clothing & carpet

• Bug-repellant clothing

• Military uniforms that change color to match the environment

• Light weight bullet-proof vests

• Clothing that scans your body for a perfect fit

Etc....

Global Positioning System-GPS

Textiles integrated with sensory devices driven by a GPS can detect a user’s exact location anytime and in any weather.

Interactive electronic textiles with integrated GPS enhance safety by quickly locating the wearer and allowing the suit to be heated.

GPS can provide added safety for firefighters and emergency personnel by facilitating offsite monitoring of vitals.

Warning Signaling A combination of sensors and small flexible light emitting displays

\(FLED) can receive and respond to stimuli from the body, enabling a warning signal to be displayed or sent.

The sensors can monitor heart rate, respiration, and temperature.

If vital signals were below critical values, a FLED would automatically display, for example, a flashing red light, and a wireless communication

system could send a distress signal to a remote location.

Thanks !

With a hope for great success of Nano Technology in Textiles …