▎ 摘　　要

NOVELTY - The preparation of modified polyamide composite fiber involves adding hexamethylenediamine and polyphosphoric acid to water, stirring, adding graphene into water, ultrasonically dispersing, leaving still, cooling, filtering, and drying the precipitated solid to obtain graphene loaded with hexamethylenediamine and polyphosphoric acid, adding to acetic acid aqueous solution, and dispersing to prepare additive solution, preparing hexamethylenediamine into an aqueous solution, adding adipic acid, and reacting to form polyamide 66 salt, and preparing polyamide 66 salt solution. USE - Preparation method of modified polyamide composite fiber. ADVANTAGE - The method enables preparation of modified polyamide composite fiber with improved strength, excellent antistatic property and aging resistance, and which maintains the original smoothness of the fiber surface without hairiness. DETAILED DESCRIPTION - The preparation method of modified polyamide composite fiber involves (a) adding hexamethylenediamine and polyphosphoric acid to water, uniformly stirring, adding graphene into water, ultrasonically dispersing, leaving still, cooling, filtering under reduced pressure, and drying the precipitated solid to obtain graphene loaded with hexamethylenediamine and polyphosphoric acid, (b) adding the graphene loaded with hexamethylenediamine and polyphosphoric acid to acetic acid aqueous solution, and ultrasonically dispersing to prepare additive solution, (c) preparing hexamethylenediamine into an aqueous solution with concentration of 25-35 %mass, adding adipic acid with molar amount equal to hexamethylenediamine, and reacting to form polyamide 66 salt, preparing polyamide 66 salt solution with concentration of 45-55 %mass, adding viscous stabilizer, decoloring using activated carbon, evaporating, concentrating, crystallizing, and drying to obtain polyamide 66 salt solid, (d) preparing polyamide 66 salt solid into an aqueous solution with concentration of 55-65 %mass, heating at 85-95 degrees C, adding additive liquid, polycondensing, cooling the polymer, extruding, granulating, and drying to obtain polyamide 66 masterbatch, and (e) spinning the polyamide 66 masterbatch.