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Polytetrafluoroethylene (PTFE)

is the chemical name for Teflon®. This is a highly saturated fluorocarbon polymer which was discovered by Roy Plunkett, a 27-year-old research chemist working at the DuPont Research Laboratories in Deepwater, New Jersey in 1938.
Two dry film lubricants compared; the competing product on the left and the smooth, even, consistent coating of MicroCare dry film lubricants on the right.
Plunkett's polymer had some remarkable properties: it was not attacked by corrosive acids, even if they were hot; it did not dissolve in solvents; it could be cooled to -240°C without becoming brittle and it could be heated to 260°C without impairing its performance. PTFE materials also are extremely stable and nonflammable; clean, dry, non-oily and non-staining. The material is biologically inert and does not support biological growth (that is, it is non-pyrogenic). For more details about PTFE, see the DuPont web site.

Plunkett also noted that the substance had a slippery feel, which is why you are reading this page today. Lubricants based on PTFE offer an extremely low static coefficient of friction, which stems from the extremely low intermolecular forces (van der Waals forces) in the PTFE molecule itself.

The molecular structure of Teflon is based on a chain of carbon atoms, the same as all polymers. Unlike some other fluoropolymers, in Teflon this chain is completely surrounded by fluorine atoms. The bond between carbon and fluorine is very strong, and the fluorine atoms shield the vulnerable carbon chain. This unusual structure gives Teflon its unique properties. In addition to its extreme slipperiness, it is inert to almost every known chemical.
 
PTFE was accidentally invented by Roy Plunkett of Kinetic Chemicals in New Jersey in 1938. While Plunkett was attempting to make a new CFC refrigerant, the perfluorethylene polymerized in its pressurized storage container, with the iron from the inside of the container acting as a catalyst. Kinetic Chemicals patented it in 1941[1] and registered the Teflon trademark in 1945
 
PTFE is a thermoplastic polymer, which is a white solid at room temperature, with a density of about 2.2 g/cm3. According to DuPont, its melting point is 327 °C (621 °F), but its mechanical properties degrade above 260 °C (500 °F).[7] PTFE gains its properties from the aggregate effect of carbon-fluorine bonds, as do all fluorocarbons.
PTFE has excellent dielectric properties. This is especially true at high radio frequencies, making it suitable for use as an insulator in cables and connector assemblies and as a material for printed circuit boards used at microwave frequencies. Combined with its high melting temperature, this makes it the material of choice as a high-performance substitute for the weaker and lower melting point polyethylene that is commonly used in low-cost applications. Its extremely high bulk resistivity makes it an ideal material for fabricating long-life electrets, useful devices that are the electrostatic analogues of magnets
 
Due to its low friction, it is used for applications where sliding action of parts is needed: plain bearings, gears, slide plates, etc. In these applications, it performs significantly better than nylon and acetal; it is comparable to ultra-high-molecular-weight polyethylene (UHMWPE), although UHMWPE is more resistant to wear than Teflon. For these applications, versions of Teflon with mineral oil or molybdenum disulfide embedded as additional lubricants in its matrix are being manufactured.
 
High-Performance Fabrics

Thin, lightweight and durable Membranes are waterproof and windproof. They may be engineered to achieve varying degrees of moisture vapor permeability or "breathability." The result: high-performance fabrics that provide a unique combination of comfort and protection.

Gore's expertise in membranes has generated a family of fabric laminates, including the GORE-TEX® and WINDSTOPPER® fabrics widely known to consumers and professionals. Today GORE fabrics are used indoors and out, by medical professionals, fire services, the military and emergency personnel, as well as hikers, skiers, cyclists and golfers.
Medical Implants

Because expanded PTFE is totally inert, GORE medical products are extremely biocompatible; the body does not reject them. The microporous structure of GORE expanded PTFE can be engineered so that surgeons and patients benefit from a wide range of healing solutions, including synthetic blood vessels and patches for soft tissue regeneration, and surgical sutures for use in vascular, cardiac, general surgery and orthopedic procedures. Our medical products work in harmony with the body's own tissues to restore normal functions.
Fluoropolymer Fibers

Gore's expanded PTFE fibers possess high strength, exhibit low shrinkage and resist abrasion. They also offer excellent resistance to degradation from ultraviolet rays. This combination of characteristics ensures stability and integrity in extreme environments.

Fibers may be knitted, woven, braided or sewn into myriad applications. Examples include compression packings, sewing thread, architectural fabric and dental floss.
Gaskets and Sealants

Expanded PTFE's resistance to chemicals and abrasion, combined with its ability to withstand high and low temperature extremes, makes it highly effective in the transport and sealing of industrial fluids.

GORE gasketing and sealant products-from flat sheets to thin tape and form-in-place sealants-are available to fit flanges of any size or configuration.
Membrane Technology for Industry

GORE's expanded PTFE membranes are engineered to unique microstructures to provide an array of high-efficiency filter media. Its pores allow air to pass through while trapping particles. Expanded PTFE's unique chemical inertness and thermal stability make it suitable for filtration conditions where exposure to harsh chemicals or high temperatures exist.

Gore filter bags, cartridges, microfiltration membranes, vents and adsorbent products address diverse contamination control and processing challenges. Industrial uses range from chemical production plants to incinerators, and from baghouses to foundries.
Advanced Dielectric Materials for Electronics

The inherently low loss and dielectric constant of expanded PTFE makes it an ideal insulation for wire and cable: Its unique porous structure allows signals to travel nearly at the speed of light with minimum loss or distortion, and it offers thermal stability and mechanical flexibility. It also lends itself to reduction in overall interconnect size and weight and provides an outstanding medium for filler materials.

Gore's electronic product portfolio today includes copper and fiber-based cables, assemblies, printed wiring board materials, conductive interface products and shielding gaskets. GORE products are found in high performance, challenging applications in the telecommunications, computing, test and measurement, defense, air and space markets, among others.

 

 

 
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