recognized as the first fluorocarbon material in the world and referred to as PTFE Molded, Sheet, Film, Plate, Rod, Tube or TFE, it is the most chemically resistant plastic known. It has a working temperature range of minus 400°F to 500°F, excellent thermal and electrical insulation properties and a low coefficient of friction.
With a non-stick surface, very few materials will adhere to it (See – Chemical Etching link below) and those that stick can easily be peeled or rubbed off. PTFE’s mechanical properties are lower than other engineering plastics, but that can be improved by adding fillers such as glass fiber, carbon, graphite, molybdenum disulfide and bronze.
Common applications include, food processing, electrical parts, insulators, medical components, seals, bearings and high heat situations.
Note: Virgin grade sheet is made from unreprocessed PTFE resin and costs more then the less expensive “mechanical grade” PTFE sheet, which is made from reprocessed PTFE resin. Modern Plastics offers both grades.
Available Fills: Glass, Carbon, Graphite, Calcium, Ceramic, Bronze, Moly-Disulphide and Colors.
Property Comparison Chart of Various Fluoropolymers -Modern Plastics
| Property | ASTM test method/test conditio | PTFE | PFA | FEP | ETFE | CTFE | ||||||||||||||||||||||||||||
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Physical Properties
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Thermal Properties |
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| Thermal conductivity (cal/sec/cm) | C177 | 6 X 10-4 | — | 6 X 10-4 | 5.7 X 10-4 |
4.7~5.3 X 10-4 |
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| Coefficient of linear thermal expansion (1/°C) | D696/23~60°C | 10 X 10-5 | 12 X 10-5 |
8.3~10.5 X 10-5 |
5~9 X 10-5 |
4.5 ~ 7.0 X 10-5 |
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| Melting point (°C) | 327 | 302~310 | 270 | 260 | 210~212 | |||||||||||||||||||||||||||||
| Melt viscosity (coise) |
10-11~10-13 (340-380°C) |
10-4~10-5 (380°C) |
4X10-4 ~10-5 (380°C) |
10-4~10-5 (300-330°C) |
10-7 (23°C) |
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Maximum temp. for continuous use (°C/°F) |
260/500 | 260/500 | 200/392 | 150/302 | 120/248 | |||||||||||||||||||||||||||||
| Mechanical Properties | ||||||||||||||||||||||||||||||||||
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Tensile strength (kgf/cm2) |
D638/23°C | 140~350 | 280~315 | 190~220 | 410~470 | 320~420 | ||||||||||||||||||||||||||||
| Elongation (%) | D638/23°C | 200~400 | 280~300 | 250~330 | 420~440 | 80~250 | ||||||||||||||||||||||||||||
| Compression strength (kgf/cm2) | D695/1% deformation, 25°C | 50~60 | 50~60 | 50~60 | 109 | 90~120 | ||||||||||||||||||||||||||||
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Tensile modulus (kgf/cm2) |
D638/23°C | 4,000 | — | 3,500 | 5,000~8,000 | 10,500~21,000 | ||||||||||||||||||||||||||||
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Hexural Modulus (kgf/cm2) |
D790/23°C | 5,000~6,000 | 6,600~7,000 | 5,500~6,500 | 9,000~14,000 | 13,000~18,000 | ||||||||||||||||||||||||||||
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Impact strength (ft-lb/ln) |
D256/23°C lzod | 3.0 | — | No breakdown | No breakdown | 2.5~2.7 | ||||||||||||||||||||||||||||
| Hardness (Shore) | Durometer | D50~D65 | D60 | D55 | D75 | D90 | ||||||||||||||||||||||||||||
| Deformation under load (%) |
D621/100°C 70 kfg/cm2, 24 hrs D621/25°C 140 kgf/cm2, 24 hrs |
5.07.0 | 2.42.7 | 5.03.0 | 5.42.3 | 2.60.2 | ||||||||||||||||||||||||||||
| Static friction coefficient | Coated steel surface | 0.02 | 0.05 | 0.05 | 0.06 | 0.08 | ||||||||||||||||||||||||||||
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Electrical Properties |
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| Dielectric constant |
D150/103Hz D150/108Hz |
2.1 2.1 |
2.1 2.1 |
2.1 2.1 |
2.6 2.6 |
2.3~2.7 2.3~2.5 |
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| Dielectric dissipation factor |
D150/103HZ D150/108HZ |
<1 X 10-5 2 X 10-5 |
1 X 10-5 3 X 10-5 |
6 X 10-5 5 X 10-5 |
8 X 10-4 5 X 10-3 |
(2.3~2.7) X10-2 1 X 10-2 |
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Dielectric breakdown strength (V/ml) |
D149/Short time, 1/8 in | 480 | 500 | 500~600 | 400 | 500 | ||||||||||||||||||||||||||||
| Volume resistivity (ohm-cm) | D257 | >10-18 | >10-18 | >10-18 | >10-18 | >10-18 | ||||||||||||||||||||||||||||
| Chemical resistance Weatherability Combustibility (%) |
D2863/Oxygen concentration index |
ExcellentExcellent > 95 |
ExcellentExcellent > 95 |
ExcellentExcellent > 95 |
ExcellentExcellent > 31 |
ExcellentExcellent > 95 |
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| Typical Filler Properties | |||
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Filler
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Physical Form
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Amount (% Weight)
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Effect of Filler
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| Glass Fibers |
Milled Fibers
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up to 40%
(also in combination with graphite, MoS2 and carbon) |
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| CarbonCarbon Fibers |
Powder Milled Fibers |
up to 25%
(also in combination with graphite, bronze, and glass) up to 30% |
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| Graphite |
Powder
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up to 25%
(also in combination with glass, bronze, and carbon) |
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| Bronze |
Powder
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up to 60%
(also in combination with carbon, graphite, and MoS2)) |
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| Molybdenum disulphide (MoS2) |
Powder
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up to 5%
(also in combination with glass and bronze) |
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| Stainless Steel |
Powder
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up to 60%
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| Pigments |
Powder
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up to 2%
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