MODIFICATION OF PROTECTIVE TEXTILES

By- NILANJAN BAGCHI (11001411019)

PRODUCT DESIGN LABGOVT. COLLEGE OF ENGG & TEXTILE TECHNOLOGY, SERAMPORE

CONTENTS

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

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

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.

What is KEVLAR

• Kevlar® a Para amide fibre, It has the iupac name poly(imino-p-phenyleneimino= terephthaloyl), It has trade name from DU PONT, 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

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

corrosion resistance

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

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.

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

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

Other Applications

Light weight Helmet,

Advanced Vehicle Armor,

Advanced materials for the oil & gas industry,

Automotive industry,

Optical cables,

Heat Resistant Gloves.

Anisotropic metamaterials

What is a meta material?• A periodic material that

derives its properties from its structure rather than its components.

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.

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.

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.

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