PES (Polyethersulfone) is a high temperature amorphous thermoplastic offering a superior combination of better chemical resistance and higher dry heat capability than polysulfone (Udel®) or polyetherimide (Ultem®). Polyethersulfone may also be referred to as Polyarylsulfone.
Polyethersulfone provides a greater margin of performance in
such areas as toughness in comparison with other plastics. It has a high heat deflection temperature of 400°F (204°C), good hydrolytic stability, and chemical resistance to many commonly used acids and bases.