FFKM Kalrez 6221 vs. FFKM Perlast G74S

Attribute	FFKM Kalrez 6221	FFKM Perlast G74S
Temperature Range	-15°C to 275°C	-20°C to 300°C
Hardness	75 Shore A	80 Shore A
Chemical Resistance	Excellent	Excellent
Compression Set	Low	Low
Tensile Strength	20 MPa	22 MPa

Introduction

FFKM Kalrez 6221 and FFKM Perlast G74S are both high-performance perfluoroelastomers that are widely used in demanding industrial applications. These materials are known for their exceptional chemical resistance, high temperature stability, and excellent mechanical properties. In this article, we will compare the attributes of these two FFKM materials to help you make an informed decision when choosing the right material for your specific application.

Chemical Resistance

One of the key attributes of both FFKM Kalrez 6221 and FFKM Perlast G74S is their outstanding chemical resistance. These materials are capable of withstanding a wide range of aggressive chemicals, including acids, bases, solvents, and fuels. However, FFKM Kalrez 6221 is known to have slightly better resistance to certain chemicals, such as hot water and steam, compared to FFKM Perlast G74S. This makes Kalrez 6221 a preferred choice for applications where exposure to these specific chemicals is a concern.

Temperature Stability

Both FFKM Kalrez 6221 and FFKM Perlast G74S exhibit excellent temperature stability, with the ability to withstand high temperatures without losing their mechanical properties. However, Kalrez 6221 has a higher upper temperature limit compared to Perlast G74S. Kalrez 6221 can withstand temperatures up to 327°C (620°F), while Perlast G74S has a maximum temperature limit of 316°C (600°F). If your application requires exposure to extreme temperatures, Kalrez 6221 may be the better choice.

Mechanical Properties

When it comes to mechanical properties, both FFKM Kalrez 6221 and FFKM Perlast G74S exhibit excellent tensile strength, tear resistance, and compression set resistance. However, Kalrez 6221 is known to have slightly better mechanical properties compared to Perlast G74S. Kalrez 6221 has higher tensile strength and tear resistance, making it a more durable and long-lasting material for applications that require high mechanical performance.

Compression Set Resistance

Compression set resistance is an important attribute for elastomeric materials used in sealing applications. Both FFKM Kalrez 6221 and FFKM Perlast G74S have excellent compression set resistance, with the ability to maintain their sealing properties over a long period of time. However, Kalrez 6221 is known to have superior compression set resistance compared to Perlast G74S. If your application requires a material that can withstand prolonged compression without losing its sealing properties, Kalrez 6221 may be the better choice.

Cost

Cost is an important factor to consider when choosing between FFKM Kalrez 6221 and FFKM Perlast G74S. Kalrez 6221 is known to be a more expensive material compared to Perlast G74S. The higher cost of Kalrez 6221 is justified by its superior chemical resistance, temperature stability, and mechanical properties. If your application requires a material with exceptional performance and durability, the higher cost of Kalrez 6221 may be justified.

Conclusion

In conclusion, both FFKM Kalrez 6221 and FFKM Perlast G74S are excellent high-performance perfluoroelastomers that offer exceptional chemical resistance, temperature stability, and mechanical properties. Kalrez 6221 has slightly better chemical resistance, temperature stability, and mechanical properties compared to Perlast G74S. However, the higher cost of Kalrez 6221 may be a limiting factor for some applications. Ultimately, the choice between these two materials will depend on the specific requirements of your application and your budget constraints.