Phenyl ether polymers are a class of polymers that contain a phenoxy or a thiophenoxy group as the repeating group in ether linkages. Commercial phenyl ether polymers belong to two chemical classes: polyphenyl ethers (PPEs) and polyphenylene oxides (PPOs). The phenoxy groups in the former class of polymers do not contain any substituents, whereas those in the latter class contain 2 to 4 alkyl groups on the phenyl ring. PPE, sometimes called PPO, is a polymer that offers excellent heat resistance, dimensional stability, and mechanical properties. PPE also has low moisture absorption and excellent hydrolysis resistance, but it can also be flame retardant. Common applications for PPE include components in printers and copiers, electrical devices like connectors and circuit breakers in vending machines, and water softeners. PPE is normally blended with PS or nylon to improve its processability.
