Polyetherimide (PEI) is a high-performance thermoplastic known for its excellent thermal stability and mechanical strength. It is often used in applications that require materials to withstand high temperatures and harsh environments, such as in the aerospace, automotive, and electrical industries. PEI is characterized by its transparency and resistance to chemicals, making it suitable for various engineering applications. Its ability to maintain structural integrity at elevated temperatures allows it to be used in components like electrical connectors and medical devices, where reliability is crucial.