Flame-retardant halogen-free polyimide films useful as thermal insulation in aircraft applications and methods relating thereto

摘要

Flame-retardant, thin gauge polyimide films are disclosed which are generally useful in lightweight, aircraft thermal insulation, or similar type applications. These films contain additives having a nitrogen-containing condensed phosphoric acid compound where the additive component is present in a thin polyimide dry film at a weight ratio of about 3 to 15 weight percent. The thickness of these flame-retarding, thin polyimide films is between 8 and 45 microns. These films have a flame retardancy rating that meets or exceeds national standards according either UL 94 Thin Material Vertical Burning Test 94VTM-0, UL 94 Thin Material Vertical Burning Test 94VTM-1 or UL 94 Thin Material Vertical Burning Test 94VTM-2.