Copper-Clad ULTEM

Polyflon’s Copper-Clad ULTEM® laminates are a specialty product for applications that can be enhanced by its unique properties, making it a better choice than alternatives.

It is made from the engineering amorphous thermoplastic Polyetherimide (PEI) that combines isotropic electrical and mechanical properties with exceptional thermal stability. The copper is fused to the dielectric – no bonding films or adhesives are used in manufacturing.


Copper-Clad ULTEM®’s specific gravity of 1.27 is much less than that of competitive PTFE/glass material. In addition, it has a variety of other preferable characteristics including:

  • A dielectric constant of 3.05 at 3 GHz
  • Dissipation factor of 0.003 at 3 GHz
  • Wide maximum operating temperature range of -55o C to +175o C
  • Excellent coefficient of thermal expansion of 56 ppm/ o C in all directions.

Available thicknesses of 0.035, 0.062, and 0.125 in. Panels are 12 in. x 18 in. Copper weight per thickness ranges from 0.50 to 2.0 oz./ft.2. ULTEM is a registered trademark of General Electric Company.

Available Documents