▎ 摘　　要

NOVELTY - Low-dielectric polyimide i.e. 2-(4-(4-(2-(4-(4-aminophenoxy)phenyl)-1,1,1,3,3,3-hexafluoropropan-2-yl)phenoxy)phenyl)-5-(2-(1,3-dioxoisoindolin-5-yl)-1,1,1,3,3,3-hexafluoropropan-2-yl)isoindoline-1,3-dione (I) is new. USE - (I) is useful in preparation of low-dielectric polyimide film for electronic packaging (claimed). ADVANTAGE - (I): reduces crosstalk and signal loss at 5G high frequency; and has low thermal expansion coefficient, excellent optical property, excellent heat resistance and mechanical property. DETAILED DESCRIPTION - Low-dielectric polyimide i.e. 2-(4-(4-(2-(4-(4-aminophenoxy)phenyl)-1,1,1,3,3,3-hexafluoropropan-2-yl)phenoxy)phenyl)-5-(2-(1,3-dioxoisoindolin-5-yl)-1,1,1,3,3,3-hexafluoropropan-2-yl)isoindoline-1,3-dione of formula (I) is new. INDEPENDENT CLAIMS are included for: low-dielectric polyimide film, comprising (I), further comprising fluorine-containing monomer to react with low-dielectric polyimide, low-dielectric polyimide film is prepared by preparing polyimide matrix material layer, and then introducing fluorinated graphene nanosheets into the polyimide material layer to obtain a low-dielectric polyimide film; and preparation of low dielectric polyimide film, comprising dissolving (I) and dibasic anhydride monomer in an organic solvent and a catalyst solvent, respectively to obtain first mixed solution and second mixed solution, mixing the first mixed solution and two mixed solutions at 45-50℃, and stirring under 2 atmospheric pressures for 25-30 minutes to obtain third mixed solution, adding dehydrating agent into the third mixed solution, and performing chemical reaction to obtain fourth mixed solution, pouring the fourth mixed solution into the heating kettle, open and heating until the water content is 10-15% to obtain slurry, casting the slurry on a glass plate to obtain (I), compounding the fluorine-containing monomer and (I) to obtain polyimide matrix material layer, introducing the fluorinated graphene nanosheets into the polyimide material layer to obtain final product.