Polytetrafluoroethylene (PTFE) sheets are a cornerstone of industrial materials, known for their exceptional chemical resistance, low friction, and outstanding thermal stability. As a semi-crystalline fluoropolymer, PTFE is a go-to material for demanding applications across aerospace, chemical processing, electronics, and food manufacturing industries. The versatility of PTFE sheets allows them to function as gaskets, seals, liners, and insulating components, providing reliable performance in environments where other materials would fail. Their inherent non-stick properties and ability to operate across a wide temperature range make them an invaluable engineering solution.
The widespread use of PTFE sheets is driven by a unique combination of properties that are difficult to find in any other single material.
Our PTFE sheets are manufactured to the highest standards, available in various grades to meet specific application requirements. Below is a detailed breakdown of our standard product specifications.
| Parameter | Standard Grade | Glass Filled (15%) | Carbon Filled (25%) | Virgin (High Purity) |
|---|---|---|---|---|
| Color | White | Tan/Brown | Black | White (Opaque) |
| Specific Gravity | 2.15 - 2.20 | 2.20 - 2.25 | 2.10 - 2.15 | 2.15 - 2.18 |
| Tensile Strength (psi) | 3,000 - 4,000 | 2,800 - 3,500 | 2,500 - 3,200 | 3,500 - 4,500 |
| Elongation at Break (%) | 300 - 500 | 250 - 350 | 200 - 300 | 350 - 550 |
| Continuous Service Temp. | -268°C to 260°C | -268°C to 260°C | -268°C to 260°C | -268°C to 260°C |
| Coefficient of Friction | 0.05 - 0.08 | 0.10 - 0.15 | 0.12 - 0.18 | 0.04 - 0.07 |
| Dielectric Strength (V/mil) | 480 - 500 | 450 - 480 | 400 - 450 | 500 - 550 |
| Common Sheet Sizes | 24" x 24", 36" x 36", 48" x 48", 60" x 60", Custom sizes available | |||
| Standard Thickness Range | 1/64" (0.4mm) to 2" (50mm) | |||
Q: What is the maximum temperature a PTFE sheet can withstand?
A: PTFE sheets can withstand continuous service temperatures up to 260°C (500°F). For short-term exposure, they can handle temperatures up to 300°C (572°F) without significant degradation. At the lower end, they remain flexible and functional down to cryogenic temperatures of -268°C (-450°F).
Q: How does PTFE compare to other fluoroplastics like PFA or FEP?
A: PTFE has a higher maximum continuous use temperature (260°C) than FEP (200°C) and similar to PFA (260°C). However, unlike PFA and FEP, virgin PTFE is not melt-processable, which limits some manufacturing techniques. PFA and FEP can be injection molded and are more transparent. PTFE generally offers the best overall chemical resistance and lowest coefficient of friction.
Q: Can PTFE sheets be machined or fabricated easily?
A: Yes, PTFE sheets are renowned for their excellent machinability. They can be easily cut, drilled, punched, skived, and stamped using standard workshop tools. Their low hardness and non-abrasive nature make them easy to work with, though sharp tools are recommended for a clean finish. Complex gaskets and custom parts are routinely manufactured from PTFE sheet stock.
Q: Are PTFE sheets safe for use in food processing applications?
A: Yes, virgin PTFE is chemically inert and is compliant with FDA regulations (21 CFR 177.1550) for repeated food contact. It is widely used for conveyor belts, release sheets, and liners in bakeries, candy manufacturing, and other food processing operations where a non-stick, non-contaminating surface is required.
Q: What is "creep" or "cold flow" in PTFE and how is it managed?
A: Creep, or cold flow, is the tendency of PTFE to deform slowly under a continuous mechanical load over time, especially at elevated temperatures. This is a characteristic of unfilled (virgin) PTFE. It is managed by using filled grades (e.g., glass, carbon, bronze) which incorporate reinforcing materials that significantly reduce creep, allowing the material to maintain its shape and dimensional stability under sustained pressure.
Q: How do I select the right thickness for my PTFE sheet application?
A: The required thickness depends on the application's mechanical and pressure requirements. For gaskets in low-pressure flanges, thinner sheets (1/32" to 1/16") are often sufficient. For heavy-duty bearings or liners in abrasive environments, thicker sheets (1/4" to 1" or more) are necessary to ensure longevity and load distribution. Consulting with an application engineer is recommended for critical applications.
Q: Is PTFE resistant to UV light and outdoor weathering?
A: Yes, PTFE has excellent resistance to ultraviolet (UV) light and weathering. It does not become brittle or significantly degrade when exposed to sunlight and harsh outdoor conditions for extended periods. This makes it suitable for architectural applications, such as membrane structures, and for outdoor electrical insulation.
Q: Can PTFE sheets be bonded or adhered to other surfaces?
A: Bonding PTFE is challenging due to its non-stick, low-surface-energy properties. Standard adhesives will not work. Successful bonding requires specialized techniques, such as surface treatment with sodium naphthalene etchants or plasma treatment to activate the surface, followed by the use of high-strength epoxies or fluoropolymer-based adhesives designed specifically for PTFE.
