These are plastics whose molecules contain sulfone groups ( SO2 ) to the main chain, as well as a variety of aromatic or aliphatic constituents such as ether or isopropylidene groups. Aliphatic polysulfones are less stable, for example, to hydrolysis, but are of interest for some biomedical applications. Four major types of polysulfones have been of commercial interest: polysulfone, polyarylsulfone , polyethersulfone and polyphenylsulfone.
The aromatic structural elements and the presence of sulfone groups are responsible for the resistance to heat and oxidation; ether and isopropylidene groups contribute some chain flexibility. In fact, the high-temperature performance of polyethersulfones is surpassed by few other polymers. Resistance to hydrolysis at high temperatures and to most acids, alkalies, and nonpolar organic solvents is excellent; however, the resins may be attacked or dissolved by polar solvents, especially if the component is under stress.
Polysulfone resins find many applications in electronic and automotive parts, medical instrumentation subject to sterilization, chemical and food processing equipment, and various plumbing and home appliance items. Coating formulations are also available, as well as grades reinforced with glass beads or fibers.
