▎ 摘　　要

NOVELTY - Graphene bubble film contains closed air hole having average diameter of 5-30 mu m. It has a thickness of 60-200 mu m, volume density of 0.1-0.3 g/cm3 and closed porosity of greater than 50%. USE - The graphene bubble film is used as an electromagnetic shielding material for electronic device (claimed). ADVANTAGE - The graphene bubble film has ensured conductivity and thermal conductivity by directly using graphene with good conductivity and thermal conductivity as substrate. When the electromagnetic wave is incident into the closed air hole, it generates reciprocating reflection in the closed air hole until exhaustion, so as to realize electromagnetic shielding. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the graphene bubble film comprising mixing graphene oxide hydrosol and pore-forming agent at 10:1-7 mass ratio, ultrasonically treating at 200-500 W for 0.5-5 hours to obtain mixed suspension; and heating the mixed suspension at 1-10 degrees C/minute and 600-3000 degrees C for 30-120 minutes.