摘要 |
A uniaxially-stretched, extruded film comprising a polyetherimide and less than 5 weight percent of fluorine, wherein the extruded film has at least one wrinkle-free region having a first surface and a second surface, the at least one extruded wrinkle-free region comprising: an extruded thickness of more than 0 and less than 13 micrometers, and a variation of the thickness of the film of +/−10% of the thickness of the film, and a surface roughness average that is less than +/−3% of the average thickness of the film as measured by optional profilometery; and further wherein the film has a dielectric constant at 1 kHz and room temperature of at least 2.7; a dissipation factor at 1 kHz and room temperature of 1% or less; and a breakdown strength of at least 300 Volts/micrometer. |