Fluoropolymer


A fluoropolymer is a fluorocarbon-based polymer with multiple carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases. The best known fluoropolymer is polytetrafluoroethylene.

History

In 1938, polytetrafluoroethylene was discovered by accident by a recently hired DuPont Ph.D., Roy J. Plunkett. While working with tetrafluoroethylene gas, he noticed that a previously-pressurized cylinder had no pressure remaining. In dissecting the cylinder, he found a mass of white solid in a quantity similar to that of the tetrafluoroethylene gas. It was determined that this material was a new-to-the-world polymer. Tests showed the substance was resistant to corrosion from most substances and had better high temperature stability than any other plastic. By early 1941, a crash program was making commercial quantities.

Properties

Fluoropolymers share the properties of fluorocarbons in that they are not as susceptible to the van der Waals force as hydrocarbons. This contributes to their non-stick and friction reducing properties. Also, they are stable due to the stability multiple carbon–fluorine bonds add to a chemical compound. Fluoropolymers may be mechanically characterized as thermosets or thermoplastics. Fluoropolymers can be homopolymers or Copolymer.

Examples of monomers used to prepare fluoropolymers

The global demand on fluoropolymers was estimated at approximately US$7.25 billion in 2011. Driven by new developments of products, applications, and processes, as well as strong demands in new markets, the demand is expected to grow by 5.8% in the following years.
Some of the world's largest manufacturers of fluoropolymers include DuPont, 3M, Solvay Chemicals, BASF and Dyneon.

Examples of fluoropolymers

Typical properties

PropertyMethod No.UnitsPTFEFEPPFAETFEECTFEPCTFEPVDF
Specific gravityD792-2.172.152.151.71.72.151.78
Yield strengthD638MPa101215.524314046
Yield strengthD638PSI1,4501,7402,2503,4804,5005,8006,670
Elongation%200-500250-350300200-500200-30080-25020-150
Tensile modulusD638MPa6005007001500165515002400
Tensile modulusD638ksi8772.5101.5217.5240218348
HardnessD2240Shore D60576275759079
HDT, @ 66 PSID648°F250158164219240248300
HDT, @ 264 PSID648°F122129118160169-239
Limiting oxygen indexD2863%>95>95>9530-36
Dielectric constantD1501 MHz2.12.12.12.6