PROJECT REPORT ONKEVLAR AND ITS APPLICATIONS

Presented By:

Himank Joshi(51) ECE Branch

What is Kevlar?

Kevlar is a material formed by combining para-phenylenediamine and terephthaloyl chloride.

Aromatic polyamide (aramid) threads are the result. They are further refined, by dissolving the threads and spinning them into regular fibres.

When woven, Kevlar forms a strong and flexible material.

If layers of the woven Kevlar® are combined with layers of resin, the resulting ‘rigid’ material is light and has twenty times the strength of steel.

Development 1964- Stephanie Kwolek and her colleagues at

DuPont began searching for a new lightweight strong fiber for light, strong tires

1965- discovery of new method of producing polymer chains

1971- high strength Kevlar(poly-paraphenylene terephthalamide) introduced by DuPont

Structure The molecular structure includes a Benzene ring which allowed formation of structures on the ring Alignment of the chains allows Kevlar to be integrated into composite materials The molecules layer themselves in such a way that in order to break through Kevlar, the molecular bonds have to be broken

Properties High modulus High tensile strength at low weight Low electrical conductivity High chemical resistance Low thermal shrinkage High toughness High cut resistance Flame resistant/self extinguishing Immune to electron radiation

UV Light- the only breaking material

Causes discoloration and degradation of the Kevlar in the presence of oxygen

Not influenced by moisture or atmospheric contaminants Damaging if the wave is absorbed by the polymer SOLUTION: It’s coated with something UV resistant

(absorbant)

Applications in Military Vehicle Armor

Spall Liners Also protects aircraft and helicopter crews

Military Helmets Absorb 20% more kinetic energy for Ground Troops Improve mobility and fatigue of GIs because of low weight

Body Armor Improved Outer Tactical Vest, ballistic inserts, throat and groin

protectors, anti-mine boots and chaps

GENERAL APPLICATIONS•Ropes and cables•Auto hoses and belts•Composite materials•Tires•Fiber optic cables•Sporting goods •Umbilical hoses on offshore oil and gas refineries•Insulation

Transportation

Aircraft

Maritime vessels

Space Applications In the Mars Pathfinder to

reinforce the inflatable landing cushions and securing ropes

> survived 40 million mile journey

Space shuttle and communications satellites to protect against impacts from orbital debris Hubble Telescope!

Space Station

Used in modules of the International Space Station (ISS) to protect from micrometeorites and orbital debris

Helps protect crew from radiation

Basic layout of module wall: 1. metal, 2. Kevlar, 3. main structure (pressure shell),4. thermal insulation

Why use Kevlar to protect the ISS?

Lightweight Low thermal expansion Resilient Woven fibers are strong and flexible

Flexibility absorbs shock from impacts

Everyday Kevlar

Fire Resistant Mattresses Personal Electronics Sports

Boarding/Skiing Baseball Hiking

THANK YOU