Polyetherimide: A new high‐performance thermoplastic resin

A new high‐performance amorphous thermoplastic, named polyetherimide, has been developed by the General Electric Company. This resin is characterized by high deflection temperature (200°C at 264 psi), high tensile strength and flexural modulus (480,000 psi), and very good retention of mechanical properties at elevated temperatures. In addition, the resin exhibits good electrical properties, which remain stable over a wide range of temperature and frequencies (including microwave). Polyetherimide is inherently flame resistant without the use of additives. It has a high limiting oxygen index of 47, combined with NBS smoke chamber results which show the lowest specific optical density of any unfilled thermoplastic (Dmax = 31). One synthetic method for the preparation of polyetherimides and a comprehensive property profile of the first member of this polymer family are presented.