Wonder Plastic- Teflon

Teflon is the very important commercial polymer formed by the repeated union of tetrafluoro ethylene monomer unit. The emulsion polymerisation method is generally employed to synthesise teflon in presence of dibenzoyl peroxide initiator.

Teflon is the most important plastic because of its extremely good properties. Teflon is the trade name for polytetrafluoroethylene. It has the linear structure (-CF2-CF2-) .The monomer used is tetrafluoro ethylene which is a non-toxic gas with boiling point -76 degree Celsius. The monomer TFE is obtained by the reaction of chloroform and hydrogen fluoride.

CHCL3 + 2HF --------CHClF2 + 2HCl

chloroform chlorodifluoro methane

2CHClF3---pyrolysis---- C2F4 +2HCl

Teflon is essentially a linear polymer without branching. It is an example for a thermoplastic that is softens on heating and hardens on cooling. Teflon is the synthetic macro molecule which plays vital role in our every day life. It shows the following unique properties:

• High degree of crystallinity.
• melting point (327 degree Celsius).
• High density.
• Practically insoluble in any solvent.
• High resistance to corrosive chemicals, oxidising and reducing agents and strong mineral acids including concentrated nitric acid.
• It is not wetted by either oil or water.
• Remains slippery over a wide range of temperature( -40 to 300 degree Celsius)
• Teflon has low coefficient of friction
• High thermal stability and good mechanical strength.
• Excellent electrical insulating properties.

Teflon is therefore rightly called as a "Wonder Plastic"

Applications of Teflon:

1. Insulating material: Because Teflon is a good electrical insulator, it has been used in wire and cable insulation, insulation of motors generators, transformers and high frequency electronic equipments.


2. Antistic applications: It is not wetted by oil or water. Teflon is coated on articles such as bakery trays, frying pans and food processing equipments.


3. Industrial filters, gaskets and belts of Teflon are used,where resistance to chemical and high temperature are required.
4. Anti corrosive coating: Teflon can be coated on metal surfaces just like paints and then heat fused. These coatings offer permanent protection against corrosion. This technique is widely used fr army weapons.

5. As a dry Lubricant : It is the ideal lubricant because it stays slippery a wide range of temperature. Teflon does not collect dust and sand. Therefore teflon is used for non lubricated bearings as a dry lubricant.