Nano technology

1. Applications of Nano technology in textiles
S M Kamrul Hasan
Assistant Professor, NITER
PhD Candidate, Donghua University
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TE 4206 : Technical Textiles and Nanotechnology

2. Before we dig into the nanotechnology and its applications in textiles,
we have to introduce ourselves with many modern terms.
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3. Technical textiles
• "Technical textiles are materials meeting high technical and quality
requirements (mechanical, thermal, electrical, durability...) giving
them the ability to offer technical functions".
or
• "Technical textile is defined as textile materials and products
manufactured primary for their technical performance and functional
properties, rather than for their aesthetic and decorative
characteristics".
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4. Types of Technical Textiles
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5. Raw materials
Raw materials used for making TT are as follows –
• Natural fibers – Cotton, Wool, Jute, Silk etc.
• Synthetic polymers – PET or PES, PA, PAN, PP, PCL, PU etc.
• Regenerated fibers – Rayon and acetate fiber.
• Minerals – Asbestos.
• Metals – Carbon, steel etc.
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6. Don’t be confused among different technical terms
• Smart textiles (Smart textiles can be defined as textiles able to sense and react to
environmental conditions and external stimuli )
• E-textiles (Electronic textiles or e-textiles are textiles that enable
electronic components such as batteries, lights, sensors, and microcontrollers to
be embedded in them )
• Both Smart and E-textiles can be considered as Technical textiles if these are
applied to those 12 categories of Technical textiles.
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7. Modern Technologies used in textiles
Technological advancements in the textile industry include the use of new
machines. For example:
• Advances in textile fabrication – 3D orthogonal weave, Spacer fabrics, Braids, 3D
printing etc.
• Advances in Dyeing- ultrasonic waves, microwave dyeing, Plasma technology,
supercritical carbon dioxide, and electrochemical dyeing of textiles
• Advances in Printing- Laser printing, Digital printing etc.
• Advances in Textile Finishing- Fire repellent, water repellent, self-cleaning finishes
etc.
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3D orthogonal weave Ultrasonic Dyeing of textiles Digital Printing of textiles Self cleaning finish on textiles

8. Nanotechnology
Nanotechnology is the manipulation of matter on a near-atomic scale (Nanoscale =
involving dimensions of < 100 nm) to produce new structures, materials and
devices.
Examples are – Nanoparticles (fig A &B), nanofluids (Fig C), nanowires (Fig D) and
nanofilms (Fig E)
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C
D
E
A
B

9. Applications of nanotechnology in textiles
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10. Other Applications
• Fire retardant.
• Color fastness.
• UV absorption.
• Energy storage.
• Color changing.
• Communication.
• Abrasion.
• Self Cleaning.
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11. Advantages of Nanotechnology in the textile industry :
• Provide comfort with enhanced functionality
• Provide a good life and contribute to industrial competitiveness all over the world
• Build the door of new industrial revolution in textile industry
• Reduce the high risk of skin cancer by using UV protection in clothing
• Anti-bacterial nanoparticles in textile is a weapon for the fight against the
spreading of antibiotics resistant germs
• The nanocarbon can be studded in antistatic clothing and packaging fabric as in
protective suits for blast protection.
• Can be used to change the color of clothing
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12. Disadvantages of Nanotechnology in textile
• As a new technology, it may also raise health, environment and safety concerns.
• There are a number of health effects of nanotechnology including pulmonary
inflammation, genotoxicity, carcinogenicity, and circulatory effects
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13. Improvements in textile by applying nanotechnology
• Improvements in Fiber/Yarn Manufacturing by using Nanotechnology
• Progress Towards the Fabric Finishing by using Nanotechnology
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14. Improvements in Fiber/Yarn Manufacturing by using
Nanotechnology
Nanofiber fabricating
• Electrospinning
-Dry Electrospinning (a) 2D, (b) 3D
- Wet electrospinning (a) 2D, (b) 3D
• Phase separation
- Non solvent Induced Phase separation
- Thermally induced Phase separation.
• 3D Printing
Nanotube synthesis
• Plasma arching
- applying an electric current across
two carbonaceous electrodes in an
inert gas atmosphere. 14

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Electrospinning
Phase separation
Improvements in Fiber/Yarn Manufacturing by using
Nanotechnology

16. 16
Improvements in Fiber/Yarn Manufacturing by using
Nanotechnology
3D Printing or rapid prototyping

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A Few Representative Textile Products Based on
Nanotechnology
Electrospun Nanofibers Phase separated Nanofibers 3D printed Nanofibers

18. Progress Towards the Fabric Finishing by using Nanotechnology
Different Types of Textile Finishes
• Temporary Finish.
• Semi-durable Finish.
• Permanent Finish.
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19. Progress Towards the Fabric Finishing by using Nanotechnology
Types of finishes
• UV Protective Finish
• Anti-pollen finishing
• Anti-bacterial finish
• Odor-fighting Finishes
• Anti-wrinkle Finishes
• Flame-retardant finishes
• Anti-static Finishes
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20. Techniques of nano-finishing on textiles
• Nano coating
a. Layer by layer assembly
b. Nano Spray
c. Pad-dry-cure
• Plasma coating
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21. Layer by Layer assembly
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Layer by Layer assembly
Positive
polyelectrolyte water Negative
Polyelectrolyte water
Repeat cycle
Substrate to be
coated

22. Spray coating
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Plasma coating

24. What is Plasma?
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• Plasma is often called “the fourth state of matter,” along with solid, liquid and
gas. Just as a liquid will boil, changing into a gas when energy is added,
heating a gas will form a plasma – a soup of positively charged particles (ions)
and negatively charged particles (electrons).
• Plasma is simply ionized gas. Gas turns into plasma when heat or energy is
added to it. The atoms that make up the gas start to lose their electrons and
become positively charged ions. The lost electrons are then able to float
freely. This process is called ionization.
• Since the particles (electrons and ions) in a plasma have an electrical
charge, the motions and behaviors of plasmas are affected by electrical and
magnetic fields.

25. SYNTHESIS OF NANOPHASE MATERIALS
There are 2 ways in synthesis of Nano phase materials they are-
• Top down approach involving breaking down the bulk materials to nano-sizes (Eg.
Mechanical alloying)
• Bottom up approach the nano-particles also made by building atom by atom
(Eg. Inert gas condensation)
One of the trends in synthesis process is to pursue nano-scale emulsification through
which finishes can be applied to textile materials in more through, even and precise
manner. Finishes can be emulsified into nano-micielles made into nano-sols (or)
wrapped in nano-capsules, that can be adhere to textile substrates more evenly.
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26. Mechanical alloying {Top-down}
• Mechanical alloying (MA) technique is one of the processes to produce
nanomaterials. This process involving milling of constituent powder in high-
energy ball mills goes extensive mechanical deformation due to ball-powder-ball
and ball-powder-container collisions that occur during MA.
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27. Inert gas condensation and pyrolysis { bottom-up }
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Thank you