PEI (poly­ether­im­ide) [Ultem®]


  • Non-crystalline ther­mo­plas­tic resin
  • Can be extruded, ther­mo­formed, extru­sion blow-molded and injection-molded
  • Heat-resistant
  • High strength and stiffness
  • Chemical-resistant
  • Avail­able in trans­par­ent and opaque cus­tom col­ors and glass-filled grades
  • Copoly­mers avail­able for more rugged conditions
  • Nat­ural grade is FDS-, NSF-, and USP Class VI-compliant
  • Low smoke-generating
  • Flame-resistant

Com­mon uses

  • Many appli­ca­tions in med­ical, electronic/electrical, microwave, auto­mo­tive and air­craft industries


Mate­r­ial Specifications

ASTM or UL test Prop­erty Value
D792 Den­sity (g/cm3) 1.27
D570 Water absorp­tion, 24 hrs (%) 0.25
D638 Ten­sile strength (psi) 15,200
D638 Ten­sile modulus -
D638 Ten­sile elon­ga­tion at break (%) 60
D790 Flex­ural strength (psi) 22,000
D790 Flex­ural mod­u­lus (psi) 480,000
D785 Hard­ness, Rockwell 109
D256 Izod notched impact (ft-lb/in) 1.0
D3418 Melt­ing temp (F°) 426
D696 Coef­fi­cient of lin­ear ther­mal
expan­sion (x 10–5 in./in./°F)
D648 Heat deflec­tion temp (F°/C°) at 264 psi 410
- Max oper­at­ing temp (F°) -
C177 Ther­mal con­duc­tiv­ity
UL94 Flam­ma­bil­ity rating V-O
D150 Dielec­tric con­stant at 1 KHz 3.15
D150 Dis­si­pa­tion fac­tor at 1 KHz 0.0013
D149 Dielec­tric strength (V/mil)
short time, & ½” thick
D257 Vol­ume resis­tiv­ity (ohm/cm) at 50% RH 1.0 x 1017

These are typ­i­cal val­ues for ref­er­ence and com­par­i­son only. They should not be used as a basis for design spec­i­fi­ca­tions or qual­ity con­trol. Con­tact us for the man­u­fac­tur­ers’ com­plete mate­r­ial prop­erty datasheets. All val­ues were taken at 73°F (23°C) unless oth­er­wise noted.

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