DAI-EL

Daikin’s DAI-EL fluoroelastomer and perfluoroelastomer products provide excellent high temperature and aggressive fluids resistance in sealing and fluid transport applications for automotive, oil and gas, aerospace, chemical process, small engine, and other harsh sealing environments. Daikin’s global technical and manufacturing resources support new developments and application of DAI-EL, each designed to meet specific OEM (end user) and fabricator (processor) requirements. In the Americas, as well as in Asia and Europe, Daikin partners with you to provide the best fluoroelastomer product solutions available in the world today.

DAI-EL: Selection Guide

Selecting a fluoroelastomer grade is often a difficult exercise in balancing performance requirements, processing considerations, and cost. To help you overcome this challenge, DAI-EL has created a selection guide with pertinent information and detailed recommendations. Whether you have a specific processing method and performance property in mind or are interested in exploring where different properties might take you, the DAI-EL selection guide is a powerful tool at your disposal. For additional information and product recommendations, please contact the DAI-EL technical service team.

DAI-EL Selection Guide

DAI-EL: Fluid Resistance Guide

Fluoroelastomers and perfluoroelastomers offer superior acid, base, chemical, and fuel resistance compared to other types of rubber. However, significant performance differences exist within these product families. To assist you in determining which grades are most suitable for your operating environment, Daikin has created a chemical resistance guide. This guide details expected performance including volume swell data in harsh operating conditions. While comprehensive, this guide is not exhaustive so for additional information please contact the DAI-EL technical service team.

DAI-EL Resistance Guide

Effect of Fluorine Content

The fluorine content of a DAI-EL grade affects many things, especially low temperature properties and fluid resistance. In general, the lower the service temperature and volume swell of a compound, the better. However, as the chart below depicts, when selecting a fluoroelastomer there is generally a tradeoff between the two properties. For low temperature operating conditions, consider selecting a DAI-EL low temperature or copolymer grade. For sealing against aggressive fluids or other media, consider a 71% fluorine terpolymer or even a perfluoroelastomer.

Bisphenol Curable Copolymers

Daikin bisphenol curable copolymers are 66% fluorine content copolymers of hexafluoropropylene and vinylidene fluoride. These products exhibit the best heat resistance and lowest compression set among the DAI-EL family. They are particularly suited for O-ring and oil seal applications in high-heat environments. Daikin offers injection and compression molding grades, extrusion grades, metal adhesion grades, and compression set resistant grades. Most DAI-EL copolymers are supplied as cure incorporated precompound but specifically labeled base polymers (BP) are available. These require the addition of a bisphenol curing agent and an accelerator.

For product information including descriptions and tech data sheets, please expand any of the tables below.

Bisphenol Curable Terpolymers

Daikin bisphenol curable terpolymers are terpolymers of hexafluoropropylene, vinylidene fluoride and tetrafluoroethylene. Their fluorine content ranges between 66% and 71%. Like the bisphenol curable copolymers, they are available as both base polymer and precompound. These polymers are ideal for applications that require resistance to fuel mixtures and solvents, such as fuel hoses and seals used in chemical processing. Compared with copolymers, cure times tend to be a little longer and compression sets a little higher, and with the exception of DAI-EL G-671 and G-EXP-025, low temperature flexibility is not as good due to higher fluorine content. Injection and compression molding grades, extrusion grades and lower temperature grades are available.

Peroxide Curable Copolymers

Daikin peroxide curable copolymers have 66% fluorine content. These products have better acid resistance and overall mechanical properties than bisphenol cured copolymers. However, there is some reduction in heat and compression set resistance for peroxide curable copolymers. Injection and compression molding grades and improved mold flow grades are available. Post curing can be omitted for these polymers.

Peroxide Curable Terpolymers

Daikin peroxide curable terpolymers have between 69% and 71% fluorine content. They have better acid resistance, solvent resistance, and overall mechanical properties than bisphenol cured copolymers. As with peroxide cured copolymers, some reduction in heat and compression set resistance is normal compared with bisphenol cured grades. Compression and injection molding, low compression set and lower temperature grades are available. Post curing can be omitted for these polymers.

Low Temperature Peroxide Curable

Daikin’s low temperature peroxide curable polymers have improved low temperature performance, mechanical properties, flex resistance, acid resistance and flex cracking resistance compared with bisphenol cured copolymers. As with other peroxide cured polymers, some reduction in heat and compression set resistance is seen compared with bisphenol cured polymers. Injection and compression molding, fluid resistant grades are available. Post curing can be eliminated for these polymers.

Base Resistant Elastomers

For some oil and gas and automotive applications the base resistance of fluoroelastomer (FKM) products is not sufficient. FEPM rubber has excellent base and amine resistance but has poor low temperature flexibility, poor fuel resistance, and slow cure speed compared to FKM. DAIKIN has developed new 62% fluorine content polymers which combine the processing advantages of FKM with amine resistance comparable to FEPM. These grades are peroxide curable and post curing can be eliminated if desired. For more information, please contact the DAI-EL technical service team today.

Perfluoroelastomers

Operating environments in the aerospace, oil & gas, chemical processing, transportation and semiconductor manufacturing industries are becoming increasingly harsh. At the same time, global competitive pressures require minimizing maintenance downtime and warranty costs. There is simply no room for failure of critical sealing components. That’s why design, process and maintenance engineers specify DAI-EL perfluoroelastomer for the toughest sealing applications. They know that seals made of DAI-EL perfluoroelastomer are more resistant to aggressive chemicals and high temperatures than any other elastomer on the market today. That means longer intervals between seal changes, reduced risk of leakage, a safer operating environment and higher productivity. DAI-EL is proud to introduce three perfluoroelastomer base polymers in addition to many compounds that satisfy OEM specifications. For more information, please contact the DAI-EL technical service team.

Specialty Elastomers

Daikin offers a pair of specialty fluoroelastomer products for unique applications where FKM or FFKM won’t suffice.

DAI-EL G-101 is a liquid fluoroelastomer and an excellent processing aid and hardness modifier. Adding a few parts per hundred rubber to a bisphenol cured copolymer compound results in smoother extrusions and moderate reduction in hardness, modulus, and tensile strength while improving elongation significantly.

DAI-EL T-530 is the first thermoplastic fluoroelastomer. Although it performs as an elastomer below its melting point, above its melting point it flows like a thermoplastic material.