Polyetherimide (PEI for short) is an amber transparent solid. It has inherent flame retardancy and low smoke without adding any additives. The oxygen index is 47%, the combustion grade is ul94-v-0, and the density is 1.28 ~ 1.42g/cm3. Pei has strong high temperature stability. Even non reinforced Pei still has good toughness and strength. Therefore, the superior thermal stability of Pei can be used to make high temperature and heat-resistant devices. It has excellent mechanical properties, electrical insulation, radiation resistance, high and low temperature resistance and wear resistance, and can pass through microwave. Pei also has good flame retardancy, chemical resistance and electrical insulation characteristics. The glass transition temperature is very high, up to 215 ℃. Pei also has low shrinkage and good isotropic mechanical characteristics. Adding glass fiber, carbon fiber or other fillers can achieve the purpose of reinforcement and modification; It can also form heat-resistant polymer alloy with other engineering plastics, and can be used for a long time at the working temperature of - 160 ~ 180 ℃.
