Fluorine rubber, commonly known as FKM, stands as a cornerstone in various industries due to its exceptional chemical resistance, high-temperature tolerance, and versatility.

From automotive to aerospace, FKM materials play a pivotal role in ensuring the longevity and reliability of crucial components. However, the efficacy of FKM is intricately tied to proper storage and handling practices.

In this blog, we delve into the significance of FKM, understanding its unique properties, factors affecting storage life, recommended shelf life for different FKM compounds, storage guidelines, and examples of real-world scenarios where improper storage impacted FKM performance.


Understanding FKM Materials

FKM, or fluorine rubber, is a synthetic elastomer known for its outstanding chemical resistance, particularly to oils, fuels, and chemicals, making it a preferred choice in industries where exposure to harsh substances is common.

Its high-temperature tolerance, low compression set, and excellent aging characteristics further enhance its appeal. Common applications for FKM include seals, gaskets, O-rings, and various other components in automotive, aerospace, and chemical processing industries.


Factors Affecting FKM Storage Life

The concept of storage life refers to the duration during which FKM materials can be stored without compromising their performance. It is crucial to recognise that storage life varies depending on the specific FKM compound.

Factors such as temperature, humidity, and the type of packaging used can significantly influence the storage life of FKM materials.


Recommended Shelf Life for Different FKM Compounds

To provide a comprehensive understanding, let's categorise FKM compounds based on their recommended shelf life.

Shelf Life

FKM Compounds

20 years or more

- Fluorosilicone

- Fluorocarbons (Viton®)

Up to 10 years

- Chlorosulfonated Polyethylene (Hypalon)

- Isobutylene/Isoprene (Butyl)

Up to 5 years

- Butadiene/acrylonitrile (Nitrile)

- Polychloroprene (Neoprene)

Making sure you store FKM materials the right way is a game-changer for their lifespan. Following those storage guidelines is like giving them a VIP treatment, ensuring they stay top-notch and reliable. It's the key to keeping FKM components performing at their peak in various critical applications.


Storage Guidelines

Maintaining optimal storage conditions is paramount for preserving the integrity of FKM materials. Here are some key storage guidelines.

Temperature Control

Importance: Temperature significantly impacts the aging process of FKM. Excessive heat accelerates degradation, leading to reduced performance and shortened lifespan.

Guideline: Keep the storage temperature below 100°F (38°C). Storing FKM in a cool environment helps prevent premature aging. Avoid placing it near direct heat sources such as radiators, boilers, or sunlight.

Why It Matters: High temperatures can break down the polymer chains in FKM, affecting its mechanical properties, chemical resistance, and overall functionality.

Humidity Management

Importance: Moisture can lead to condensation, which greatly affects FKM materials. It may cause swelling, softening, or even mould growth.

Guideline: Maintain relative humidity levels to prevent condensation. Store FKM away from areas prone to dampness or high humidity.

Best Practices:

  • Use dehumidifiers if necessary.
  • Avoid storing FKM in basements or areas with fluctuating humidity.
  • Ensure proper ventilation to minimize moisture buildup.


Appropriate Packaging

Importance: Proper packaging shields FKM from external factors like light, dust, and contaminants.

Guideline: Utilise polyethylene bags for individual FKM components. Place these bags inside cardboard containers or polyethylene-lined craft paper bags.

Why It Matters:

  • Polyethylene Bags: These prevent direct exposure to light and dust, preserving FKM’s surface quality.
  • Cardboard Containers: Provide structural support and prevent physical damage.
  • Polyethylene-Lined Craft Paper Bags: Offer additional protection against moisture and contaminants.


Regular Inspections

Importance: Even well-stored FKM materials can degrade over time. Regular checks help identify signs of deterioration or contamination.

Guideline: Schedule periodic inspections to assess stored FKM components.

What to Look For:

  • Visual Changes: Check for discoloration, cracks, or surface irregularities.
  • Odour: Unusual smells may indicate chemical reactions or contamination.
  • Physical Integrity: Ensure packaging remains intact.
  • Storage Environment: Confirm that temperature and humidity conditions are within the recommended range.

Remember, proper storage practices not only extend the lifespan of FKM materials, but also contribute to their consistent performance. Implementing these guidelines ensures that your FKM compounds remain reliable and ready for use when needed.


Handling FKM Compounds

To work with FKM, you do not need any special equipment or environments, as long as you follow the FKM guidelines, which are a set of rules and procedures for calculating the strength and fatigue of FKM components.

The FKM guidelines provide a uniform and structured way to evaluate the static and dynamic loads, the stress and strain levels, the material properties, and the safety factors of FKM components. You can use standard FKM mixing and processing equipment, such as mixers, mills, presses, or ovens, to produce FKM components for most applications.

However, you must be careful to prevent contact with incompatible substances that could contaminate or damage the FKM material. Some of these substances are ethers, ketones, bases, amines, steam, and hot water. If FKM comes into contact with these substances, it could degrade, swell, crack, or lose its properties. Therefore, you should always clean and store FKM components properly, and avoid exposing them to harsh environments or media.


Storage Do’s and Don’ts


  • Store away from direct heat sources such as boilers, radiators, and sunlight.
  • Record cure dates for thermoset elastomers.
  • Perform periodic checks to identify any issues promptly.



  • Exceed recommended storage temperatures.
  • Allow condensation due to high humidity.
  • Neglect proper packaging, as it serves as a protective barrier against environmental factors.

By understanding and implementing these recommendations, users can safeguard the longevity and reliability of FKM components, ensuring they perform at their best when called upon in critical applications.


Final Thoughts

The importance of following proper FKM storage and handling guidelines cannot be overstated. Proper storage conditions, periodic checks, and adherence to recommended shelf-life categories are integral to maximising the lifespan of FKM materials. By implementing best practices, industries can ensure the reliability and longevity of components crucial to their operations.

If you have any more questions, would like to purchase FKM products, or would like to speak to an expert about custom solutions, don’t hesitate to contact us today.