ETFE

The "miracle polymer" for public architecture

ETFE(Ethylene Tetra Fluoro Ethylene)

MOHAMED ASLAM.TMUHAMMED SHAFEED .C

INTRODUCTION• originally developed by DuPont over 40 years ago

as an inert coating material for the aerospace industry.

• ETFE has a wide range of applications from wiring insulation, thermoplastic lining, corrosion protection to wire covers, mold release films.

• One of the primary uses of ETFE though, is in the building industry.

• The first application in the building industry took place in Europe.

The tremendous potential of ETFE had been shown with three major projects

1. The Eden Zoo project in 1998

Cont’d...

The tremendous potential of ETFE had been shown with three major projects

2. The Allianz Arena for the 2006 Soccer World

Cup

Cont’d...

The tremendous potential of ETFE had been shown with three major projects

3. The “Water Cube” at the 2008 Beijing Olympics,

Cont’d...

WHAT IS ETFE FILM? The new generation material which goes

beyond glass

ETFE (ethylene tetrafluoroethylene )film durable, transparent

Lightweight than glass, avoid danger associated with glass

Traditionally used in green houses, agriculture

Recently in fabric architecture

ADVANTAGES OF ETFE FILM

STRUCURAL SYSTEM OF ETFE

Single Layer type Film reinforced with wire

cables

Or with lightweight steel or aluminum

maintain shape and stability

Small structure such as panels shelters

Multilayer type like balloons

Sending air between 2or 3 layers

Structurally stable

Ventilation facility necessary for maintain shape

Improving thermal properties

Single layer Multi layer

The foil cushions can be inflated with an air hose and pump system

Most ETFE cushion facades are inflated to a pressure between 200-600 Pa

Once the air hose is attached to the cushion it is inflated using a central air pump system that monitors the cushion’s internal pressure, temperature, and humidity

the cushion’s pressure can be adjusted to adapt to number of external stimuli

Life

Excellent life expectancy as it is unaffected by UV light, atmospheric pollution and other forms of environmental weathering.

No degradation or loss of strength has occurred and there is no sign that the material will become brittle or discolour

life expectancy in excess of 50 years.

Excessive bird pecking can cause small punctures in the ETFE cushions.

Poses no threat to the stability of the cushion as a whole system is supplied with built in active monitoring which will automatically adjust to compensate for the slight drop in pressure.

As a precaution, structures are supplied with bird wire deterrent to stop bird perching on the extrusion/steelwork.

ACOUSTICS

Rain noise can be suppressed using a rain attenuation layer added to the top surface of the cushions

Acts as a dampener, stopping the sound reverberating around the space below.

In general, the installation of a rain attenuation layer is only necessary in exceptional circumstances.

ETFE film has approximately 70% acoustic transmission

RAIN WATER & DRAINAGE

All ETFE structures are designed with curvature to ensure that rainwater does not pond or collate on the top of the membrane as this leads to deformation of the foil

Rainwater will be channeled to the perimeter of the roof where it can be collected in the main gutter system.

COST EFFECTIVE

Due to the lightweight nature of ETFE, substructure support systems and concrete foundations can be designed more efficiently.

ETFE systems also provide ample natural day lighting, thus minimizing energy costs by lowering the demand for indoor lighting.

CHEMICAL PROPERTIES

PRIMARY INGRADIENT IS FLUORITE

FLUORITE

HYDROGENSULPHIDE+TRYCHLOROMETHANEChlorodifluoromethane

TETRAFLUOROETHYLENE+ETHYLENE

ETFE

PYROLYSIS

FLUORITE

TETRAFLUOROETHYLENE

ETHYLENE

ETFE

AMORPHOUSE AND CRYSTALINE NATURE

AMORPHOUSE INCREASES FLUX LIFE

OR FATIGUE LIFE UNTIL FAILURE

CRYSTALINE DECREASES THE RESISTENCE TO FATIUGE

30-70

33

PERFLUOROPOLYMER

ETFE is considered a partially fluorinated polymer

ADDIRTION HYDROGEN

INCREASE HARDNESS AND TOUGHNESS

DECREASES THERMAL STABILITY

LESS SUSCEPTIBLE TO CREEP

it with ample toughness and flexibility to be used as a pneumatic cushion

ETFE DURABILITY AND FLEXIBILITY

Being able to elongate between 250-650% to maintain its tension stability despite and large deflection

ETFE absorbs all structural movements by constantly conforming to changing geometries

Inflated cushion -dampens the effects of sudden win- reducing wind design

MECHANICAL PROPERTIES

Mechanical Properties Min Max Units

Modulus of Elasticity 300 1100 MPa

Poisson's Ratio 0.43 0.45  

Elastic Stress 15 18 MPa

Yield Stress 25 35 MPa

Ultimate Stress 40 64 MPa

Fracture Strain 250 650 %

Service Temperatures -200 150 C

Melting Temperature 250 280 C

Hardness 31 33 MPa

Density 1.7 1.77 g/cm3

MECHANICAL PROPERTIES

WIEGHT

DESIRABLE PROPERTY IS LIGHT WEIGHT

ONE FIOL LAYER 1% GLASS WEIHT

LESS WEGHT – LARGER SPAN OF SUPPORT

EXTRA FOIL-Inflated cushion, Aluminum extruded flashings, Inflation tubing system,

ROOF WEIGHT IS VERY LIGHT THAN GLASS ROOF

FIRE PERFORMENSE

ETFE has the unique property of self-venting the products of combustion to the atmosphere

HOT GASES IMPINGING ON CUSHION –SOFTEN AND LOSE STRENTH

TENSION MEMBER UNDER INFLATION FAILS AND SHRINK BACK TO PLUME-VENT TO ATMOSPHERE

QUANTITY IS SMALL-SELF EXTINGUSHING

ANY DRIP OF ETFE IS NON BURNING AND ARE PREVENTED FROM FALLING TO GROUND

Light Transmittance ETFE Foil is naturally a very transparent material

and transmits light across the entire visible light region (380-780nm)

Transmission across the ultraviolet range is also very good and therefore allows plants and vegetation underneath to thrive.

Absorbs a large proportion of infra red light transmitted

Solar Control

1.Printing: Foils can be printed with an infinite variety of shading patterns that can block out light at varying amounts throughout the day

By varying the percentage of coverage and density of the ink, the energy transmission can be altered

Clear ETFE Pattern Printed

on ETFE

2. Additional Layer : The outer and middle layer, within a three-layer system, can be printed with positive and negative patterns that let light through when the foils are separated and repel light

The position of the middle layer is controlled by the relative air pressures between the two chambers.

INSULATION

Originally developed as wire insulation for extreme temperature and chemical environments,

ETFE surpasses the insulation value of glass

Further increased by introduction of air pocket

These act as double or triple layer glass

Insulation value can be increase or decrease by adjusting air

MAINTANCE

LESS EXPENSIEVE THAN GLASS DU TO NON STICK PROPERTY

ETFE IS THE SMOOTHEST SUBSTENCE KNOWN TO MAN

SELF CLEANING PROPERTY- REDUCE REGULATR NEED OF CLEANSING SERVICE

DUST OR MINERALS WASHED OUT IN RAIN

ETFE SO LIGHTWEIGHT – NO NEED OF SCAFFOLDING OR LIFTING EQUIPMENT FOR REPLACEMENT

SERVICING THE ROOF WITH WORKERS NOT PROBLAMATIC

RECYCLING

EASY, ENERGY EFFICIENT , MAKING THE PROCESS OF REUSING OLD CUSHION IS VIABLE

LOW MELTING OPERATION VERY IN EXPENSIEVE

ONCE MOLTED , ETFE CAN BE EXTRUDED IN TO SINGLE LAYER USED IN CUSHION FOIL

GLASS IS RECYCLABLE FLOAT GLASS USED FOR ARCHTECHTURAL PURPOSE

SENSITIVE TO IMPURITEIS WHEN RECYCLED GLASS WITH VIRGIN GLASS

DECORATION LED’s that can communicate written

messages on the cushions

CONCLUSION

ETFE can prefabricated with a plug-in jointing system that offers a high degree of precision and can be delivered to the construction site as a series of small components .

What is clear that the world is not short of architects who want to specify ETFE in their project

ETFE continues to open new horizon for architects and it is sure to remain for foreseeable future

THANK YOU