|Material Guide
Material Guide

What Is Ultem (PEI)? High-Temperature Aerospace-Grade Plastic

Ultem earns its place by meeting requirements most engineering thermoplastics cannot satisfy simultaneously — continuous service at 340°F, a UL 94 V-0 flame rating without additives, inherent biocompatibility, and transparency in its natural amber form.

Published March 2026·Plastic-Craft Products
Ultem PEI rod and sheet stock in natural amber color
Certified ISO 9001:2015 AS9100:2016 FAR 25.853 Compliant Grades
01

What Is Ultem?

Ultem is SABIC's trade name for polyetherimide (PEI) — an amorphous thermoplastic with excellent dimensional stability, optical clarity in thin sections, and consistent performance without directional property variation. Naturally amber-transparent in unfilled form.

Common grades: Ultem 1000 (unfilled general purpose), Ultem 1010 (medical/food-grade, autoclave-rated), Ultem 2300 (30% glass-fiber-filled for enhanced stiffness).


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Key Properties

Continuous service temperature: 340°F (170°C) — significantly higher than nylon, Delrin, or polycarbonate.

Flame resistance: UL 94 V-0 without flame-retardant additives. Meets FAR 25.853 for aircraft interior materials. Low smoke and toxic gas in combustion.

Biocompatibility: Ultem 1010 is certified biocompatible and rated for repeated steam autoclave sterilization at 270°F (132°C).

Mechanical strength: High tensile and flexural strength maintained at elevated temperatures.

Dimensional stability: Very low moisture absorption, excellent creep resistance.

Electrical insulation: Excellent dielectric properties across temperature and frequency ranges.

The primary trade-off vs PEEK is chemical resistance. Ultem is susceptible to certain halogenated solvents and strong bases. For applications requiring both extreme temperature and broad chemical resistance, PEEK remains stronger. For applications where flame performance is the driver, Ultem is often preferred — at a lower cost.


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Applications

✈️
Aerospace Interiors
🏥
Medical Sterilization Equipment
Electrical & Electronics
🏭
Industrial High-Temperature
🛡️
Defense & Military
🔬
Laboratory Equipment

Aerospace interiors: Brackets, ducts, housings, and panels where FAR 25.853 flame/smoke/toxicity compliance is required.

Medical: Ultem 1010 for instrument trays, surgical tool handles, and device housings requiring repeated steam autoclave cycles.


04

Grades

Ultem 1000

Standard unfilled general purpose. High-temperature structural, electrical, and industrial applications.

Ultem 1010

Medical and food-contact grade. Certified biocompatible. Rated for repeated steam autoclave sterilization. Do NOT substitute 1000 for 1010 in autoclave applications.

Ultem 2300

30% glass-fiber-filled. Additional stiffness and dimensional stability under high sustained loads. Reduced impact resistance. More tooling wear.


FAQ

Frequently Asked Questions

What is the difference between Ultem 1000 and 1010?

Ultem 1000 is standard general-purpose. Ultem 1010 is medical/food-contact grade certified for biocompatibility and repeated autoclave sterilization. For any autoclave or body-contact application, 1010 is required — 1000 is not a substitute.

How does Ultem compare to PEEK?

PEEK offers higher service temperature (480°F vs 340°F), broader chemical resistance, and better fatigue performance. Ultem offers better inherent flame retardance, lower smoke/toxicity, transparency, and lower cost. Ultem for aerospace flame applications; PEEK for extreme chemical/thermal environments.

Is Ultem FAA-approved for aircraft interiors?

Ultem meets FAR 25.853 flammability requirements by virtue of inherent UL 94 V-0 rating and low heat release/smoke/toxicity. Widely used in commercial and military aircraft. Specific program qualification depends on component design and testing.

Can Ultem be sterilized by autoclave?

Ultem 1010 is rated for repeated steam autoclave sterilization. Standard 1000 can withstand limited exposure but is not rated for repeated cycles. Always specify 1010 for autoclave applications.

Where can I buy Ultem?

Plastic-Craft Products stocks Ultem in rod, sheet, and tube at West Nyack, NY. No minimum orders. Call (845) 358-3010 or email [email protected].

Ready to Order Ultem?

Plastic-Craft stocks Ultem PEI in a full range of grades and sizes — cut to exact dimensions or machined to print with no minimum orders and ISO/AS9100D certified quality for aerospace, defense, and medical programs.

(845) 358-3010

UltemPEIPolyetherimideAerospaceMedicalFlame RetardantAutoclaveFAR 25.853