▎ 摘　　要

NOVELTY - Graphene multilayer composite heat insulation film comprises a graphene layer, a flexible macromolecule film layer, a silica sol layer and a glass fiber reinforced silica aerogel layer arranged sequentially from top to bottom. USE - The heat insulation film is useful in preparation of a graphene electric heating film (claimed) used in living areas such as heating floor, building heating and far-infrared healthcare medical. ADVANTAGE - The heat insulation film adopts excellent thermal and mechanical properties of graphene to enhance insulation of external heat and strength, can be used as the graphene electric heating film after left and right ends of the graphene layer are connected with copper sheet electrodes and provides the graphene electric heating film with uniform heating, low use voltage and excellent electric heating performance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for preparing the composite heat insulation film involving (i) uniformly mixing graphene powder, a water-soluble resin, a defoaming agent, a leveling agent and a film-forming additive to obtain a graphene slurry, (ii) coating the graphene slurry to the surface of the flexible macromolecule film and drying to form a graphene layer and (ii) bonding the surface coated with the graphene layer with a silica sol binder with a glass fiber reinforced silica aerogel and drying to obtain the composite heat insulation film; and (2) a graphene electric heating film comprising the composite heat insulation film and conductive electrode, where the conductive electrode is arranged at both ends of the graphene layer in the composite heat insulation film.