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English Synonyms

1. High Temperature Resistance

2. Mechanical Properties

3. Self-Lubricating Property

4. Corrosion Resistance

5. Flame Retardancy

6. Processability

7. Processing Method of PEEK

8. Additional Characteristics

• Radiation resistance, stable insulation, hydrolysis resistance, compression resistance, and corrosion resistance. Mechanical parts made of its composite materials have a self-lubricating effect.
• Excellent temperature resistance and thermal stability, ultra-high heat resistance (superior to PPS), heat distortion temperature (HDT) above 315°C, and a continuous service temperature of 250°C (per UL standards).

1. Mechanical properties: PEEK is a plastic that balances toughness and rigidity. In particular, its excellent fatigue resistance under alternating stress is unmatched among all plastics, comparable to alloy materials.
2. Self-lubricating property: PEEK has outstanding sliding performance among all plastics, suitable for applications requiring low friction coefficient and wear resistance. Especially, PEEK modified by mixing carbon fiber and graphite in a certain proportion has better self-lubricating performance.
3. Chemical resistance (corrosion resistance): PEEK has excellent chemical resistance. Among common chemicals, only concentrated sulfuric acid can dissolve or damage it, and its corrosion resistance is similar to that of nickel steel.
4. Flame retardancy: PEEK is a highly stable polymer. A 1.45mm thick sample can meet the highest flame retardant standard without adding any flame retardants.
5. Peel resistance: PEEK has good peel resistance, so it can be made into thin coatings or electromagnetic wires and used under harsh conditions.
6. Fatigue resistance: PEEK has the best fatigue resistance among all resins.
7. Radiation resistance: It has strong resistance to high radiation, exceeding polystyrene (the resin with the best radiation resistance among general-purpose resins). It can be made into high-performance products that maintain good insulation after being exposed to a γ-radiation dose of up to 1100 Mrad.
8. Hydrolysis resistance: PEEK and its composite materials are not chemically affected by water or high-pressure steam. Products made of this material can maintain excellent performance when used continuously in high-temperature and high-pressure water.

Product Properties

• High temperature resistance: PEEK resin has a high melting point (334°C) and glass transition temperature (143°C), with a continuous service temperature of 260°C. The heat distortion temperature under load of its grades reinforced with 30% glass fiber (GF) or carbon fiber (CF) is as high as 316°C.
• Mechanical properties: PEEK plastic raw material resin has good toughness and rigidity, and its fatigue resistance under alternating stress is comparable to that of alloy materials.
• Flame retardancy: The flammability of a material refers to its ability to maintain combustion after being ignited by a high-energy mixture of oxygen and nitrogen. The recognized standard for measuring flammability is UL94, which involves igniting a vertical sample of a predetermined shape and measuring the time it takes for the material to self-extinguish. PEEK has a UL94 rating of V-0, the highest level of flame retardancy.
• Smoke generation: The standard for measuring smoke generated by plastic combustion is ASTM E662. This standard uses the smoke laboratory of the National Bureau of Standards (NBS) to measure the visible light obscuration caused by smoke from the combustion of a standard-shaped sample, in units of specific optical density. The test can be conducted with continuous combustion (with flame) or interrupted combustion (without flame). Among plastics, PEEK has the lowest smoke generation.
• Toxic gas emission: Like many organic materials, PEEK mainly produces carbon dioxide and carbon monoxide when decomposed at high temperatures. The British aircraft test standard BSS 7239 can detect extremely low concentrations of toxic gas emissions. This test involves completely burning 100 grams of a sample in a 1-cubic-meter space and then analyzing the toxic gases produced. The toxicity index is defined as the ratio of the total concentration of toxic gases produced under normal conditions to the lethal dose for humans within 30 minutes. The index of PEEK 450G is 0.22, and no acidic gases are detected.
• Dimensional stability: PEEK plastic raw material has excellent dimensional stability, which is crucial for certain applications. Changes in environmental conditions such as temperature and humidity have little impact on the dimensions of PEEK parts, allowing them to meet the requirements of working conditions with high dimensional accuracy.
  1. PEEK has a small injection molding shrinkage rate, which is very beneficial for controlling the dimensional tolerance range of PEEK injection-molded parts, making the dimensional accuracy of PEEK parts much higher than that of general-purpose plastics.
  2. It has a small coefficient of thermal expansion. The dimensions of PEEK parts change slightly with temperature variations (caused by changes in ambient temperature or frictional heat generation during operation).
  3. Good dimensional stability: The dimensional stability of plastic refers to the ability of engineering plastic products to maintain stable dimensions during use or storage. This dimensional change is mainly caused by the 卷曲 of chain segments when the activation energy of polymer molecules increases.
  4. PEEK has outstanding hot water hydrolysis resistance. It has low water absorption in high-temperature and high-humidity environments, and does not exhibit significant dimensional changes due to water absorption, unlike general-purpose plastics such as nylon.
• Insulation stability: PEEK resin has good electrical insulation properties, which are maintained over a wide temperature range. Its dielectric loss is also small at high frequencies.
• Radiation resistance and peel resistance: PEEK resin has good radiation resistance and peel resistance, so it can be used to manufacture electromagnetic wires for special purposes.

Physical Properties

• Density: 1.265 (amorphous) ～ 1.320 (crystalline) g/cm³
• Impact strength (notched): 60 ～ 80 J/m
• Elongation at break: ≥ 150%
• Water absorption: ≤ 0.1%
• Volume resistivity: 10¹⁶ Ω·cm
• Flexural strength: ≥ 140 MPa
• Dielectric constant: 3.2 ～ 3.3
• Tensile strength: ≥ 93 MPa
• Flame retardancy (UL94): V-0

Major Manufacturers of PEEK Products

• Victrex (UK)
• Amoco (USA)
• Evonik (Germany, offering VESTAKEEP powder products)

Key Features of Crystalline PEEK

• Density of crystalline PEEK: 1.32 g/cm³.
• Its most prominent feature is excellent heat resistance. Among all engineering plastics, it has the best hot water resistance and steam resistance. It can be used continuously in steam at 200 ～ 240°C or temporarily in high-pressure steam at 300°C.
• It has excellent chemical resistance, as well as good insulation and radiation resistance.

Chemical Properties

Applications

1. Aerospace field: PEEK can be processed into various high-precision aircraft components. Due to its good hydrolysis resistance, corrosion resistance, and flame retardancy, it can be made into internal/external parts of aircraft and many components of rocket engines.
2. Automotive manufacturing: PEEK has been successfully used in the automotive industry. With its good wear resistance, it can replace metals (including stainless steel and titanium) to manufacture engine covers, automotive bearings, seals, and brake pads.
3. Industrial field: Owing to its good mechanical properties, high temperature resistance, wear resistance, and pressure resistance, PEEK is often used to manufacture compressor valve plates, piston rings, and seals.
4. Medical devices: PEEK can withstand 3000 cycles of high-pressure sterilization at 134°C. This property meets the requirements for manufacturing surgical and dental equipment that require high sterilization standards and repeated use. In addition, its creep resistance and hydrolysis resistance allow it to be used in the production of various medical devices that need to be sterilized with high-temperature steam. More importantly, PEEK is non-toxic, lightweight, and corrosion-resistant, and is the material closest to human bones. Therefore, PEEK can be used instead of metals to manufacture human bones.
5. Insulating materials: PEEK has excellent electrical properties. Even under harsh conditions such as high temperature and high humidity, its insulation performance remains stable, making it an ideal electrical insulating material, especially widely used in the semiconductor industry.
6. As a new type of engineering plastic, it can be used as a high-temperature resistant structural material and electrical insulating material, and can be compounded with glass fiber or carbon fiber to prepare reinforced materials.
7. Modified PEEK: There are modified PEEK varieties such as black carbon fiber-reinforced conductive PEEK, red carbon fiber-reinforced conductive PEEK, mineral-reinforced PEEK, glass fiber-reinforced PEEK, and PEEK resin.

Limitations and Modification of PEEK

• Blending PEEK with polyether can improve its mechanical properties and flame retardancy.
• Compounding PEEK with PTFE to make composite materials results in outstanding wear resistance, which can be used to manufacture sliding bearings, dynamic seal rings, and other components.
• Filling and modifying PEEK with carbon fiber or other materials to make reinforced PEEK composite materials can greatly improve the material’s hardness, rigidity, and dimensional stability.

Comprehensive Application Advantages