In this study, we present a facile method of fabricating graphene oxide (GO) filmson the surface of polyimide (PI) via layer-by-layer (LBL) assembly of charged GO. The positively charged amino-phenyl functionalized GO (APGO) is alternatively complexed with the nega-tively charged GO through an electrostatic LBL assembly process. Furthermore, we investi-gated the water vapor transmission rate and oxygen transmission rate of the prepared (reduced GO [rGO]/rAPGO)10 deposited PI film(rGO/rAPGO/PI) and pure PI film.The water vapor transmission rate of the GO and APGO-coated PI composite filmwas increased due to the intrinsically hydrophilic property of the charged composite films.However, the oxygen trans-mission rate was decreased from 220 to 78 cm3/m2·day·atm, due to the barrier effect of the graphene filmson the PI surface. Since the proposed method allows for large-scale production of graphene films, it is considered to have potential for utiliation in various applications.

• Seon-Guk Kim(Carbon Convergence Materials Research Center, Institute of Advanced Composites Materials, Korea Institute of Science and Technology, Department of BIN Fusion Technology and Department of Polymer and Nano Science and Technology, Chonbuk National University)
• Ok-Kyung Park(Carbon Convergence Materials Research Center, Institute of Advanced Composites Materials, Korea Institute of Science and Technology, Department of BIN Fusion Technology and Department of Polymer and Nano Science and Technology, Chonbuk National University)
• Joong Hee Lee(Department of BIN Fusion Technology and Department of Polymer and Nano Science and Technology, Chonbuk National University) Corresponding Author
• Bon-Cheol Ku(Carbon Convergence Materials Research Center, Institute of Advanced Composites Materials, Korea Institute of Science and Technology) Corresponding Author