Kevlar is a para-aramid synthetic fiber known for its high strength-to-weight ratio and heat resistance. It is used in protective clothing like bulletproof vests (1). Modern technologies like honeycomb structures and liquid body armor incorporate Kevlar to provide lightweight protection (2). Further developments aim to make protective fabrics even lighter, smarter, and more effective through materials like titanium-dipped tri-weave fabrics (3). Metamaterials are periodic structures that derive properties from their structure rather than just their components, and could enable applications like invisible cloaking through controlling light (4). The protective textiles market provides opportunities but also demands extensive testing due to safety critical applications (5).

1. MODIFICATION OF PROTECTIVE
TEXTILES
By- NILANJAN BAGCHI
(11001411019)
PRODUCT DESIGN LAB
GOVT. COLLEGE OF ENGG & TEXTILE TECHNOLOGY, SERAMPORE

2. CONTENTS
I. INTRODUCTION,
II. What is KEVLAR,
III. Modern Technologies,
IV. Further Developments,
V. Anisotropic Metamaterials

3. Textiles are no more limited for use as apparels, clothing is just are but not the
only purpose of textiles with the rapid changes in the social economic
structure of our society. Many efforts are made to some and protect human
life. Protective textiles are the fastest growing area of textile consumption in
the world. As per the market survey it has projected an average growth rate of
4% for technical textiles during the period 2000-2010. At present, India’s
contribution in this area is negligible at about 0.2%.However, due to
competition from neighbouring countries as emerging economic power, India
has tremendous potential for production, Consumption and export of
Protective textile.
INTRODUCTION

4. Textiles for protection is the fruit of a diverse body of talents, drawing together
scientific and technical expertise from around the world, to produce an important
source of current knowledge on textile materials and clothing, and their use in the
protection of humans in hostile environments.

5. What is KEVLAR
• Kevlar® a Para amide fibre, It has the iupac name poly(imino-p-phenyleneimino=
terephthaloyl), It has trade name from first commercialised in 1972.
• High Tensile Strength at Low Weight
• Low Elongation to Break
• High Modulus (Structural Rigidity)
• High Chemical Resistance
• Excellent Dimensional Stability
• High Cut Resistance
• Flame Resistant, Self-Extinguishing

6. Honeycomb core technology
• Composites made with Kevlar®
• Mainly used for aerospace and marine application
• Provides lightweight strength, stiffness, toughness,
corrosion resistance

7. Liquid body armour
• Use of shear stress fluid
Behaves like liquid in normal condition but solidifies in millisecond when
strikes.
 Silicon particles suspended in polyethylene glycol.
 Enclosed between different Kevlar® sheets

8. Further Developments
To make a protective fabric functioning wisely, it has to be “lighter, smarter, deadlier”.
For this reason further developments occurred in protective fabric , like Kevlar Bi-
Weave, Titanium dipped Tri-Weave, Hardened Kevlar plates, Overlapping of ceramic
discs with kevlar. In a fun example of life imitating art, the US Air Force is developing
what it's calling the "Battlefield Air Targeting Man-Aided knowledge," or BATMAN.

9. In Aerospace
• Kevlar® helped Airbus‘ which is concept of the world's largest
aircraft to become a reality," said Jim Weigand
• Mainly used for weight reduction & increase fuel efficiency.
• It is found flooring to interior walls to wing flap to engines

10. In Marine
• Light weight providing strength, stiffness and toughness
• Versatile options for hulls, superstructures
• and furniture bulkheads
• Ideal for economies of fuel and/or increased
payloads
High impact and fatigue resistance

11. Other Applications
Light weight Helmet,
Advanced Vehicle Armor,
Advanced materials for the oil & gas industry,
Automotive industry,
Optical cables,
Heat Resistant Gloves.

12. Anisotropic metamaterials
What is a meta material?
• A periodic material that
derives its properties from its
structure rather than its
components.

13. Properties Of Meta Materials:
• They are assemblies of multiple individual elements fashioned from conventional
microscopic materials such as metals or plastics, but the materials are usually
arranged in periodic patterns.
• Their precise shape, geometry, size, orientation and arrangement can affect the
waves of light or sound in an unconventional manner, creating material
properties which are unachievable with conventional materials.
• The primary research in meta materials investigates materials with
negative refractive index.

14. Invisibility Using Meta Materials
• The things which our eyes are not able to see are considered as
“Invisible.
• Light is neither absorbed nor reflected by the objects, passing like
water flowing around a rock
• Meta-material is a type of composite material that has unusual
electromagnetic properties.
• According to the researchers, light rays incident on the material
would be bent around the object, only to emerge on the other side
in exactly the same direction as they began.

15. Applications
• There'd be plenty of applications in the
civilian world as well, even for rudimentary
cloaking devices.
• For example, you could create receptacles
to shield sensitive medical devices from
disruption by MRI scanners, or build cloaks
to route cellphone signals around
obstacles.
• Potential applications of meta materials
are diverse:
• remote aerospace applications,
• sensor detection and infrastructure
monitoring,
• smart solar power management,
• public safety, radomes, high-frequency
battlefield communication .
• lenses for high-gain antennas,
improving ultrasonic sensors, and
even shielding structures from
earthquakes.

16. The Protective textile market is respective to innovative new products. There is
opportunity and need for functional, cost-effective materials. But the market is
fragmented and complex. Development and lead times are often long and expensive.
The market is quite small but exhibits moderately strong growth and produces are
generally of high unit values. Due to increasing health and safety issues at work this
may be an increasingly attractive segment. Good products are needed and they must
work well. It is a market that offers opportunity, but also one that demands that much
development and testing be done prior to adopting new products. There may be long
lead times much resistance to things new products to market. The truth is, we can not
afford not to have the ideas and products.
Conclusion