Udel polysulfone (PSU) from Solvay is a nearly water-clear polymer with higher heat resistance than polycarbonate; Udel PSU has a deflection temperature of 174°C.
Polysulfones have long been known for transparency and clarity, but their desirability for automotive headlamp lenses has been hampered by the slight yellow cast heretofore typical of the material. Solvay’s Udel P-1700 HC is a new low-colour grade of PSU specifically engineered to be nearly water-clear.
In general, Udel PSU is a tough, rigid, high strength, high heat thermoplastic with properties that are retained at temperatures from -101°C to 149°C. The heat deflection temperature at 1.82 MPa is 174°C. Other key properties of PSU include resistance to acid and alkaline chemicals. In addition, the resin is resistant to a wide range of cleaners and disinfectants, alcohols and aliphatic hydrocarbons.