RANGE POLYETHERIMIDE - PEI -
Characteristics of the PEI
SPECIFIC CHARACTERISTICS
High heat stability.
Exceptional mechanical strength and elastic
modulus.
High dielectric strength.
Stable dielectric constant and dissipation factor.
Good chemical resistance.
Flame resistance inherent to the molecular
structure, low smoke emission.
Good machining and finishing characteristics.
Transparency.
PEI has excellent resistance against gamma
radiation, 6% loss of tensile strength after
cumulative exposure to 500 megarads at a rate of
1 Mrad/h using cobalt 60.
A 1000-hour ageing test with a xenon lamp had
no effect on tensile strength.
Approvals:
- DIN4102 Flammability Class B1
- Class M1 under the CSTB standard
- Class 0 under the BS 476 standard
Easily to metallise.
Excellent electrical insulator, high dielectric
strength (33 KV/mm at a thickness of 1.6 mm).
Good dielectric constant, remains stable
throughout PEI's usage temperature range.
Arc resistance value of 128s when subjected to
the ASTM-D495 test.
• Mil - C 55 302 • Mil - C - 83 513 • Mil - S - 83
734. • Mil - S - 83 502 • Mil S 83 505 • Mil - M -
245 19 B (EC)
SPECIFIC PROPERTIES
PEI has an exceptional flexural modulus (3300
N/mm² at room temperature), which remains
excellent at high temperatures.
Yield point at elastic limit exceeds 105 N/mm².
Furthermore, PEI's tensile strength is still approx.
40 N/mm² at 175°C, with a flexural modulus of
2300 N/mm².
PEI has remarkable toughness.
PEI's continuous use temperature is 180°C.
Its heat distortion temperature under a load of
1.82 N/mm² is 200°C.
Glass transition temperature (Tg) of 215°C.
PEI is inert with regard to most hydrocarbons,
although it is soluble in partially halogenated
hydrocarbons (methylene chloride and
trichloroethane).
It resists well against freon-based cleaning
agents, refrigerants, and vapour phase soldering
products.
PEI resists against:
- mineral acids
- mineral saline solutions
- diluted bases (pH below 9)
Prolonged immersion in water, even at 100°C,
has practically no effect on its properties.
PEI is UV-resistant.
Under the UL 94 standard, PEI has V0
classification under 0.8 mm thick and 5V
classification under 1.9 mm thick.
It gives off very little smoke, and its products of
combustion are no more toxic than those
released by wood. They consist mainly of CO,
CO², and gaseous H²O.