▎ 摘　　要

NOVELTY - Composite film or layer comprises: a polymer matrix; and graphene nanosheets dispersed in the polymer matrix at greater than or equal to 0.1 vol.%. USE - The composite film or layer is useful as a material (claimed) such as packaging material for air- and light-sensitive products. ADVANTAGE - The composite film: utilizes the graphene nanosheets that densify polymer matrix even when present at lesser concentrations and lowers the free volume within the polymer matrix and reduces oxygen solubility, thus exhibiting reduced gas permeability and light transmittance, and significantly enhancing the barrier properties of the packaging materials in a simple and economical manner; increases the shelf life of perishable goods and products including foodstuffs and pharmaceuticals such as vitamins, drugs and orthopedic implants. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a dispersion comprising polymer-treated reduced graphite oxide nanosheets dispersed in a dispersing medium; and (2) a material comprising a polymer-treated reduced graphite oxide nanosheet.