Thermalux is Westlake’s family of sulfone polymers. These amorphous thermoplastics are known for their toughness and stability at broad range of end-use temperatures from -40°C to 204°C (-40°F to 400°F). Thermalux polymers are used in specialty applications and often are a superior replacement for polycarbonates. Three types of Thermalux are commercially available: polysulfone (PSU), polyethersulfone (PESU), and polyphenylsulfone (PPSU).