▎ 摘　　要

NOVELTY - Process for producing polyimide film with high thermal stability, involves (i) adding phenyltrimethoxysilane to toluene, placing in an ice-water bath, stirring, dripping dilute hydrochloric acid, increasing temperature to 0-15 degrees C, stirring and reacting, leaving still, removing lower layer, and washing upper layer to prepare an intermediate (I) solution, (ii) dripping solution (a) to solution of intermediate (I), stirring and reacting, washing, distilling, removing solvent, and vacuum-drying to obtain an intermediate (II), (iii) adding nano-filler to mixed solution (b), heating, adding trimellitic anhydride, stirring, adding 4,4'-methylene bis (phenyl isocyanate), heating, stirring and reacting, adding phenol, heating, stirring and reacting to obtain a compound (III) solution, and (iv) adding intermediate (II) to compound (III) solution, ultrasonically dissolving, stirring, performing antifoaming treatment, scraping on substrate, air-drying, and thermally imidizing. USE - The process is used for producing polyimide film with high thermal stability. DETAILED DESCRIPTION - Process for producing polyimide film with high thermal stability, involves (i) adding phenyltrimethoxysilane to toluene, placing in an ice-water bath, stirring at a constant speed, dripping dilute hydrochloric acid, increasing the temperature to 0-15 degrees C, stirring at a constant speed and reacting for 24 hours, leaving still until separates, removing the lower layer, and washing the upper layer with deionized water until neutral to prepare an intermediate (I) solution, (ii) dripping solution (a) to the solution of intermediate (I), increasing the temperature to 70-80 degrees C, stirring at high speed and reacting for 24 hours, washing the product with deionized water to neutrality, distilling under reduced pressure, removing the solvent, and vacuum-drying at 60-80 degrees C and a vacuum of -0.10 MPa for 10 hours to obtain an intermediate (II), (iii) adding nano-filler to mixed solution (b), ultrasonically processing at room temperature at a frequency of 60 kHz for 30 minutes, heating at 90 degrees C, uniformly stirring, adding trimellitic anhydride, stirring at a constant speed until dissolves, adding 4,4'-methylene bis (phenyl isocyanate), heating at 120 degrees C, stirring at a constant speed and reacting for 4 hours, adding phenol, heating at 150 degrees C, stirring at this temperature at a constant speed and reacting for 6 hours to obtain a compound (III) solution, and (iv) adding the prepared intermediate (II) to the compound (III) solution, ultrasonically dissolving for 30 minutes, stirring at high speed for 2 hours to prepare a mixed solution, performing antifoaming treatment, scraping on the substrate, air-drying, and thermally imidizing.