Fluoroplastics for High-Performance Industrial Applications
Fluoroplastics are a class of paraffinic polymers that have some or all of the hydrogen replaced by fluorine. The fluoroplastic group in this catalog includes: FEP, fluorinated ethylene propylene; Kel-F, polychlorotrifluorethylene; PVDF, polyvinylidene fluoride; Rulon, forms of TFE fluorocarbon; TFE, virgin and mechanical, polytetrafluoroethylene; Tefzel, a modified copolymer of ethylene and tetrafluoroethylene; and Turcite.
The fluoroplastic group is characterized by excellent chemical resistance, excellent heat resistance, good electrical properties, and excellent wear resistance.
The chemical resistance of this group is unequaled by almost any other substance. Its virtual inertness to most chemicals make it an excellent choice for applications in corrosive environments. Fluoroplastics also retain their structural integrity at extremely high or low temperatures, i.e., +500 degrees F to (-110 degrees F) for Teflon. Because it absorbs little electrical energy, it excells as an electrical insulation material.
However, despite these attributes, perhaps the most desired characteristic of this group of plastics is their ability to resist abrasion. Simply stated, here is a chemist’s explanation for this unique property: A tightly bonded, impenetrible shield of fluorine atoms surrounds and protects an interior chain of carbon atoms. Unlike other materials, whose molecules lock into each other then break off when sliding takes place, these molecules have very little attraction for other substances. Result: No body takes place and there is an extremely low coefficient of friction.
Fluorocarbons may be filled or alloyed to enhance certain mechanical properties such as modular and strength. The desirable fluorocarbon properties of chemical and heat resistance are generally retained, but the price is, of course, greater for a filled fluoroplastic.
The unique chemical, electrical, thermal, and surface characterisitics make fluorocarbons ideally suited to a myriad of engineering uses which no other plastic has achieved. This group is available in a wide range of profiles, including: sheet, rod, tubing, and film.
| FEP | KEL-F | PFA | PVDF KYNAR |
RULON | TEFZEL | TFE | TURCITE | |
|---|---|---|---|---|---|---|---|---|
| PHYSICAL | ||||||||
| SPECIFIC GRAVITY | 2.12 – 2.17 | 2.08 – 2.185 | 1.75 – 1.79 | 2.24 | 1.7 | 2.1 – 2.3 | 1.50 | |
| WATER ABSORPTION, 24 hr. (%) | <0.01 | 0.00 | 0.00 | 0.00 | <0.03% | 0.00 – .005 | .06 | |
| MECHANICAL | ||||||||
| TENSILE | ||||||||
| Strength, Yield (10³ psi) @ 73°F | 3.0 – 4.0 | 5.7 | 3.6 | 5.0 – 7.0 | 12 | 6.5 | 1.5 – 5.0 | 5.5 |
| Elongation, Ultimate (%) @ 73°F | 300 | 150 | 300 | 50 – 250 | 100 | 300 | 75 – 350 | 12 |
| Modulus, Yield (10³ psi) @ 73°F | 207 | 200 – 350 | 50 – 90 | |||||
| FLEXURAL | ||||||||
| Strength (10³ psi) @ 73°F | 8.5 | 6.6 – 16.0 | No break | 11.7 | ||||
| Modulus, Yield (10³ psi) @ 73°F | 95 | 180 | 90 | 180 – 337 | 140 | 90 – 110 | ||
| COMPRESSIVE STRENGTH | ||||||||
| 2% Offset (10³ psi) | 5.5 | |||||||
| IMPACT STRENGTH | ||||||||
| Izod, Notched (ft-lb/in.) @ 73°F | No break | 5.0 D55 | 3.0 – 6.0 D76-80 | 6.0 D60-75 | R10-20 | D75 | ||
| HARDNESS | ||||||||
| COEFFICIENT OF STATIC FRICTION | ||||||||
| Against steel | 14 – 17 | 0.4 – 1.0 | ||||||
| Against itself | ||||||||
| THERMAL | ||||||||
| CONDUCTIVITY (BTU/hr/sq ft/°F/in.) |
1.0 | 7.0 – .87 | 2.3 | |||||
| COEFFICIENT OF THERMAL EXPANSION (10⁻⁶/°F) |
3.99 | 5.4 | 6.6 | 14 | 5.5 – 7.5 | 5.5 | ||
| SPECIFIC HEAT (BTU/lb/°F) |
0.215 | 30 – 34 | ||||||
| HEAT DEFLECTION TEMP (°F) | ||||||||
| At 66 psi | 158 | 258 | 257 – 284 | 100 – 140 | ||||
| At 264 psi | 167 | 188 – 239 | ||||||
| MAX. CONTINUOUS TEMP (°F) | 400 | 380 | 300 | 550 | 500 | 160 | ||
| ELECTRICAL | ||||||||
| VOLUME RESISTIVITY (Ohm-cm) |
>10¹⁶ | 1.2 × 10¹⁴ | 5 × 10¹⁴ | 1 × 10¹⁵ | >10¹⁷ | |||
| DIELECTRIC STRENGTH (V/mil) |
2100 | 500 | 4000/5000 | 260 – 1280 | 7000 | 500 – 650 | ||
| DIELECTRIC CONSTANT | ||||||||
| At 60 Hz | 2.1 | 3.0 | 2.06 | 10.0 | 2.6 | 2.0 – 2.1 | ||
| At 1 MHz | 2.1 | 2.5 | 2.06 | 7.5 | 2.6 | 2.0 – 2.1 | ||
| DISSIPATION FACTOR | ||||||||
| At 60 Hz | 0.002 | 0.005 | 0.050 | 0.004 | ||||
| At 1 MHz | 0.007 | 0.007 | 0.184 | |||||
| ARC RESISTANCE (SECONDS) | 300 | 360 | 300 | 180 – 240 | ||||