What Is Polyetherimide (PEI)? Properties & Tubing

What is Polyetherimide (PEI)?

Polyetherimide (PEI) is an amorphous high-performance polymer. It is heat and hydrolysis resistant and can withstand multiple autoclaving cycles.

Its characteristics are similar to those of polyetheretherketone (PEEK) but PEI is less temperature-resistant and has lower impact strength.

Polyetherimide is one of the high-performance engineering resins we extrude for medical tubing that needs strength, heat resistance or stiffness. Compare it with the other resins on our engineering resins page, or call us to talk through your application.

Polyetherimide tubing

Polyetherimide, often called PEI, is valued in medical devices because it withstands multiple autoclave cycles without losing its properties. It behaves much like PEEK, with somewhat lower temperature resistance and impact strength, which can make it a practical alternative for rigid reusable components. Compare it with other engineering resins.

Polyetherimide questions, answered

Does polyetherimide have a melting point?

Polyetherimide is amorphous, so it softens over a range instead of melting sharply. Its glass transition temperature is 410°F (210°C) to 421°F (216°C).

What is the density of polyetherimide?

Polyetherimide has a specific gravity of 0.0459 lb./in.3 (1.27 g/cc), which corresponds to a density of about 1.27 g/cm³.

How can polyetherimide tubing be sterilized?

Depending on grade, polyetherimide is compatible with cold sterilization, dry heat, ethylene oxide (EtO), gamma radiation and steam autoclaving. Confirm the method for your specific grade with the resin supplier.

Does Microspec extrude polyetherimide tubing?

Yes. We extrude polyetherimide into custom medical tubing, including multi-lumen, bump and co-extruded designs. Send us your print or call 603.924.4300 for a quote.

Polyetherimide (PEI) properties

Typical values, measure low to measure high
Property	Measure low	Measure high
Specific gravity	0.0459 lb./in.3 (1.27 g/cc)
Melting point	Not applicable
Glass transition temperature	410°F (210°C)	421°F (216°C)
Tensile strength at break	Not available
Elongation at break	60%	80%
Hardness durometer (Shore A)	125
Hardness durometer (Shore D)	109	112
Water absorption @ 24 hours	0.25%

This material datasheet is presented for reference only. Characteristics and performance may vary for a specific application and environment. Confirm material selection and suitability against your own requirements and the resin supplier's documentation.

Sterilization

Cold sterilization Dry heat Ethylene oxide (EtO) Gamma radiation Steam autoclaving

Polyetherimide (PEI)