▎ 摘　　要

NOVELTY - Preparing flame-retardant conductive composite polyimide film involves mixing carbon-based conductive filler with solvent and dispersant, crushing and grinding to obtain uniform first filler dispersion; adding phosphorus flame retardant material into deoxidizing solvent, carrying out ball milling dispersion, after filtering, performing high power ultrasonic treatment to obtain uniform second filler dispersion; mixing first filler dispersion with second filler dispersion according to proportion, crushing and grinding to obtain composite filler slurry; adding diamine monomer into solvent, stirring and adding composite filler slurry, after uniformly mixing, adding dianhydride monomer, namely preparing composite polyamic acid solution with certain viscosity; coating composite polyamic acid solution on substrate for curing, namely obtaining flame-retardant conductive polyimide film; and directly heating and solidifying program. USE - Method for preparing flame-retardant conductive composite polyimide film. ADVANTAGE - The method enables to have good conductivity and good flame retardant, forms complexation/bonding effect, reduces hydrogen free radical, realizes synergistic flame retardant effect, and improves safety coefficient. DETAILED DESCRIPTION - Preparing flame-retardant conductive composite polyimide film involves mixing carbon-based conductive filler with solvent and dispersant, crushing and grinding to obtain uniform first filler dispersion; adding phosphorus flame retardant material into deoxidizing solvent, carrying out ball milling dispersion, after filtering, performing high power ultrasonic treatment to obtain uniform second filler dispersion; mixing first filler dispersion with second filler dispersion according to proportion, crushing and grinding to obtain composite filler slurry; adding diamine monomer into solvent, stirring and adding composite filler slurry, after uniformly mixing, adding dianhydride monomer, namely preparing composite polyamic acid solution with certain viscosity; coating composite polyamic acid solution on substrate for curing, namely obtaining flame-retardant conductive polyimide film; directly heating and solidifying program; or, peeling pre-cured film from substrate, curing at high temperature by drying tunnel; keeping temperature for 0.2-1 hours at 150-250℃; where technique of high temperature solidifying is to raise temperature to 300-450℃ at speed of 1-8℃/minute; where carbon-based conductive filler is carbon black, carbon nano-tube, graphene, graphite alkyne and fullerene, carbon black is conductive carbon black having particle diameter of 10 nm-10 microns; thickness of graphene 1-50 nm, sheet diameter is 100 nm-10 microns of single-layer graphene or graphene, graphene is pure graphene, reduction oxidation graphene length of carbon nano-tube is 1-50 m, diameter is 2-100 nm, and carbon nano-tube is amination carbon nano-tube, nitrogen-doped carbon nano-tube, carboxylated carbon nano-tube, hydroxylated carbon nano-tube, and carbon nanotube is single-wall carbon nano tube, double-wall carbon nano-tube or multi-wall carbon nano-tube; phosphorus flame retardant material is black phosphorus, phosphate and phosphite ester, black phosphorus is obtained by processing black phosphorus, and size of black phosphorus is 100 nm-50 microns, thickness of sheet layer is 1-100 nm; first filler is 5-60 wt.% polyimide, and dispersant is polyvinyl pyrrolidone, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate and 0.1-2 wt.% polyimide filler, and oxygen removing solvent is inert organic solvent bubbling for 2-5 hours; ball milling zirconium ball particle diameter is 0.1-5 mm, ball milling dispersing time is 1-24 hours, frequency of ultrasonic dispersing is 5-40 kHz, power is 500-6000 watt, ultrasonic processing time is 1-24 hours, and ultrasonic processing temperature is 20-30℃. An INDEPENDENT CLAIM is included for a flame-retardant conductive composite polyimide film, which is prepared by preparation method, where limit oxygen index of conductive composite polyimide film reaches 66.2%.