FKM vs. TPU

Attribute	FKM	TPU
Chemical Structure	Fluorinated elastomer	Thermoplastic polyurethane
Temperature Resistance	High	Medium
Flexibility	Good	Excellent
Hardness	Varies	Varies
Chemical Resistance	Excellent	Good

Introduction

Fluoroelastomers (FKM) and thermoplastic polyurethane (TPU) are two popular materials used in various industries for their unique properties and applications. Understanding the differences between FKM and TPU can help in selecting the right material for specific requirements. In this article, we will compare the attributes of FKM and TPU in terms of their chemical composition, physical properties, applications, and more.

Chemical Composition

FKM is a type of synthetic rubber that contains fluorine atoms, which provide excellent resistance to chemicals, oils, and high temperatures. It is known for its exceptional performance in harsh environments and is commonly used in applications where resistance to aggressive fluids is required. On the other hand, TPU is a versatile polymer that combines the properties of plastic and rubber. It is composed of alternating hard and soft segments, giving it flexibility, durability, and good mechanical properties.

Physical Properties

FKM exhibits high temperature resistance, with continuous operating temperatures ranging from -20°C to 200°C. It also has excellent resistance to oils, fuels, and chemicals, making it suitable for applications in the automotive, aerospace, and oil & gas industries. TPU, on the other hand, has a wide range of hardness levels, from soft and flexible to hard and rigid. It offers good abrasion resistance, tear strength, and flexibility, making it ideal for applications such as footwear, sports equipment, and medical devices.

Mechanical Properties

FKM has good mechanical properties, including high tensile strength, elongation at break, and compression set resistance. It maintains its properties over a wide temperature range and is resistant to compression set, making it suitable for sealing and gasket applications. TPU, on the other hand, has excellent elasticity and resilience, allowing it to return to its original shape after deformation. It also has good impact resistance and flexibility, making it ideal for applications that require durability and shock absorption.

Applications

FKM is commonly used in applications that require resistance to high temperatures, chemicals, and oils, such as seals, gaskets, O-rings, and hoses in the automotive and aerospace industries. It is also used in oil & gas applications, where exposure to harsh chemicals and extreme temperatures is common. TPU, on the other hand, is used in a wide range of applications, including footwear, sports equipment, medical devices, and industrial components. Its versatility and flexibility make it suitable for various consumer and industrial products.

Cost and Availability

FKM is generally more expensive than TPU due to its specialized chemical composition and manufacturing process. It is often used in high-performance applications where resistance to harsh environments is critical. TPU, on the other hand, is more cost-effective and readily available in various grades and formulations. It is widely used in consumer products and industrial applications where flexibility, durability, and impact resistance are required.

Conclusion

In conclusion, FKM and TPU are two versatile materials with unique properties and applications. FKM offers excellent resistance to high temperatures, chemicals, and oils, making it ideal for demanding environments. TPU, on the other hand, provides flexibility, durability, and good mechanical properties, making it suitable for a wide range of consumer and industrial applications. Understanding the differences between FKM and TPU can help in selecting the right material for specific requirements and ensuring optimal performance in various applications.