▎ 摘　　要

NOVELTY - Preparation of high conductive and high electromagnetic shielding flexible composite material involves freezing oxidized graphene at - 50 degrees C to - 20 degrees C for 10-24 hours, freeze-drying for 72-100 hours to obtain oxide graphene sponge, reducing graphene oxide sponge by hydrazine reducing agent steam and compressing to 0.1-10 mm with pressure of 1-100 KPa. USE - Method for preparing high conductive and high electromagnetic shielding flexible composite material (claimed). ADVANTAGE - The product has good flexibility and good electromagnetic shielding performance which can reach up to 59 dB (2 mm) and has conductivity of 1.03 S/cm. DETAILED DESCRIPTION - Preparation of high conductive and high electromagnetic shielding flexible composite material comprises: (A) freezing oxidized graphene at - 50 degrees C to - 20 degrees C for 10-24 hours and freeze-drying for 72-100 hours to obtain oxide graphene sponge; (B) reducing graphene oxide sponge by hydrazine reducing agent steam; (C) compressing to 0.1-10 mm with pressure of 1-100 KPa; (D) carrying out heat treatment at 750-1000 degrees C for 1-5 hours under inert gas protection; (E) placing in polydimethyl dilution, vacuumizing with pressure of In 10-30 MPa at an interval of 5-30 minutes, removing, putting on the shelf for 40-150 minutes; and (F) placing in a vacuum box at 30-200 degrees C and curing for 10-300 minutes to obtain polydimethylsiloxane/graphene sponge composite material where polydimethyl dilution is prepared by mixing polydimethylsiloxane matrix resin and curing resin at mass ratio of 10:1, placing in a vacuum box at pressure of 10-30 MPa for 10-40 minutes vacuumizing, adding acetone, magnetically stirring for 10-40 minutes, placing into the vacuum box with pressure of 5-20 MPa for 5-30 minutes to obtain polydimethyl dilution with acetone mass content of 5-30 wt.%.