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Radel® PPSU


Get the Performance You Need

Our family of sulfone polymers includes Radel® PPSU, Veradel® PESU and Udel® PSU. They are amorphous thermoplastic resins that combine excellent thermal stability, high strength and toughness, excellent hydrolytic stability, transparency, and good resistance to environmental stress cracking. Acudel® modified PPSU offers additional cost and performance advantages. 


Heat Resistance

Sulfone polymers are noted for high heat deflection temperatures (HDT) and outstanding dimensional stability. They are the only thermoplastics that remain transparent at service temperatures as high as 204°C (400°F). Even after long-term exposure, the resins do not discolor or degrade. 



Hydrolytic Stability

Hydrolytic stability has special importance because water is ubiquitous and very aggressive to many polymers. Sulfone polymers have excellent resistance to hydrolysis with Radel® PPSU exhibiting exceptional performance. When combined with high heat resistance, Radel® PPSU delivers long-lasting performance in hot water and steam, even under autoclave pressures. 



Chemical Resistance

Sulfone polymers have good chemical resistance to many materials, including aqueous systems, caustics, inorganic acids, aliphatic hydrocarbons, detergents and soaps, and certain alcohols. 

Sulfone polymers exhibit varying levels of chemical resistance, depending upon their polymeric structure and the presence of additives such as glass. Other factors influencing chemical resistance include the reagent, reagent concentration, temperature, exposure time and whether the polymer is under stress. 

General indication of chemical resistance | 7-day immersion at 23°C (73°F)




Radel® PPSU resins can be processed following standard methods for injection molding, extrusion, and blow molding. Shapes can be machined for prototype evaluations; film and sheet can be thermoformed on conventional equipment. Plus, you can do most post-fabrication operations such as ultrasonic welding, adhesive bonding, and laser marking as well as heat staking, threading, and machining.

Sulfone polymers will absorb moisture, and although they are hydrolytically stable, they should be dried before processing. Processing wet resin will result in cosmetic defects, such as surface streaks or splay marks on injection molded parts and severe bubbling or streaking in extruded profiles. The moisture does not hydrolyze the polymer or degrade its properties. Parts formed from undried resin are only unsatisfactory in appearance, or in some cases weak due to formation of internal bubbles. Any unsatisfactory parts due to these cosmetic defects can be reground, dried, and then remolded without loss of properties.