▎ 摘　　要

NOVELTY - A graphene-based long fibers comprise chemically functionalized graphene sheets which are chemically bonded or interconnected with one another having an inter-planar spacing (d002) of 0.36-1.5 nm measured by X-ray diffraction and a non-carbon element content of 0.1-47 wt.%. The functionalized graphene sheets are substantially parallel to one another and parallel to a fiber axis direction. The graphene sheets comprise no core-shell structure, and helically arranged graphene domains. The graphene sheets have a length of 0.5 cm or more, and a physical density of 1.5-2.2 g/cm3. USE - Graphene-based long fibers used for producing fiber yarn or bundle (claimed). ADVANTAGE - The graphene-based long fibers have improved tensile strength, elastic modulus, thermal conductivity, and electroconductivity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for fiber yarn or bundle, which comprises graphene-based long fibers and optionally comprising polyacrylonitrile-derived or pitch-derived carbon fibers. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view explaining production of multiple continuous graphene fibers from functionalized graphene sheets.