▎ 摘　　要

NOVELTY - A multifunctional diffusion barrier comprises greater than or equal to 1 organic polymer and 0.01-99.9 wt.% two-dimensional (2D) graphene or 2D graphene derivative material, each of graphene or graphene derivative material having lateral size of 0.1 mu m to 1 mm and surface area of 20-2600 m2/g, where multifunctional diffusion barrier comprises gradient concentration of 2D graphene or 2D graphene derivative material. USE - A multifunctional diffusion barrier for use as liquid and/or gas barrier, structural material, sealing material, self-cleaning material, or protective material against UV radiation in aeronautical, automotive, marine, or building field, and for use in aircraft fuel tank, fuel tank conduit, and/or gasket (all claimed). ADVANTAGE - The gradient concentration of 2D graphene or 2D graphene derivative material avoids the abrupt material changes at different levels through the thickness of the multifunctional diffusion barrier (MDB) depending on the particular profile, and provides uniform and continuous mechanical and thermal properties, while maintaining the barrier properties of the MDB. The major amount of 2D graphene or 2D graphene derivative material located at or near the outermost surface of the multifunctional diffusion barrier improves the barrier properties of the MDB on the region, such as the mechanical properties of the outermost surface. Moreover, the gradient concentration produces optical properties while retaining the improved barrier properties of the multifunctional diffusion barrier. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of multifunctional diffusion barrier.