▎ 摘　　要

NOVELTY - Producing a continuous graphitic fiber involves preparing a graphene oxide gel of living graphene oxide molecules or functionalized graphene chains dissolved in a fluid medium; dispensing and depositing at least a continuous filament of the gel onto a supporting substrate by mechanical stress-induced molecular alignment of the living graphene oxide molecules or functionalized graphene chains along a filament axis direction; removing the fluid medium from the filament to form a continuous graphene oxide fiber; and heating it at greater than 100 degrees C. USE - For producing continuous graphitic fiber (claimed). ADVANTAGE - The graphitic fiber has an oxygen content less than 1 (preferably less than 0.01, more preferably less than or equal to 0.001) %, an inter-graphene spacing less than 0.345 (preferably less than 0.337, more preferably less than 0.336) nm, a thermal conductivity of at least 1000 (preferably at least 1200, more preferably at least 1500, especially greater than 1700) W/mK, an electrical conductivity greater than or equal to 2000 (preferably greater than or equal to 3500, more preferably greater than or equal to 8000, especially greater than 15000) S/cm, a mosaic spread value of less than 1 (preferably less than or equal to 0.7, more preferably less than or equal to 0.4) and a degree of graphitization greater than or equal to 40 (preferably greater than or equal to 80) %. The continuous graphitic fiber has an electrical conductivity greater than 3000 (preferably greater than 5000, more preferably greater than 15000, especially greater than 18000) S/cm, a thermal conductivity greater than 600 (preferably greater than 1000, more preferably greater than 1500, especially greater than 1700) W/mK, a physical density greater than 1.7 (preferably greater than 1.8, more preferably 1.9) g/cm3, a Young's modulus greater than 60 (preferably greater than 200, more preferably greater than 300, especially greater than 600) GPa, and/or a tensile strength greater than 1.2 (preferably greater than 3.2, more preferably greater than 5, especially greater than 8) GPa. The process provides high-strength and high-modulus continuous graphitic fibers by using particles of natural graphite or artificial graphite as the starting material. The process is a coagulation-free process and produces graphene oxide gel-derived unitary graphene filament that exhibits a combination of exceptional thermal conductivity, electrical conductivity, mechanical strength, and elastic modulus unmatched by any continuous graphene fibers or carbon fibers. The process providing continuous graphitic fiber is cost-effective. The graphitic fiber is a neat graphene or graphitic material without any binder, resin, matrix, or glue. DETAILED DESCRIPTION - Producing a continuous graphitic fiber involves (A) (1) preparing a graphene oxide gel of living graphene oxide molecules or functionalized graphene chains dissolved in a fluid medium, where the graphene oxide molecules contain an oxygen content higher than 10 wt.%, (2) dispensing and depositing at least a continuous filament of the gel onto a supporting substrate, where the dispensing and depositing procedure includes mechanical stress-induced molecular alignment of the living graphene oxide molecules or functionalized graphene chains along a filament axis direction, (3) removing the fluid medium from the filament to form a continuous graphene oxide fiber, where the fiber has an inter-plane spacing d002 of 0.4-1.2 nm as determined by X-ray diffraction and an oxygen content greater than or equal to 10 wt.%, and (4) heating the continuous graphene oxide fiber to form the continuous graphitic fiber at greater than 100 degrees C to an extent that an inter-plane spacing d002 is decreased to 0.3354-0.4 nm and the oxygen content is decreased to less than 5 wt.%; (B) preparing a graphene oxide or functionalized graphene solution having living graphene oxide molecules or functionalized graphene chains dissolved or dispersed in a fluid medium, where the graphene oxide molecules contain an oxygen content higher than 5 wt.%, dispensing and depositing at least a continuous filament of the graphene oxide or functionalized graphene solution onto a supporting substrate by mechanical stress-induced molecular alignment or ordering of the living graphene oxide molecules or functionalized graphene chains along a filament axis direction, removing the fluid medium from the continuous filament to form a continuous graphene oxide or functionalized graphene fiber, and heating the continuous graphene oxide or functionalized graphene fiber to form the continuous graphitic fiber at higher than 100 degrees C such that an inter-plane spacing d002 is decreased to 0.3354-0.4 nm and the oxygen content is decreased to less than 5 wt.%; or (C) preparing a graphene suspension having graphene sheets dispersed in a fluid medium, dispensing and depositing at least a continuous filament of the graphene suspension onto a supporting substrate under the influence of a stress field to induce alignment or ordering of the graphene sheets along a filament axis direction, removing the fluid medium from the continuous filament to form a continuous graphene fiber containing closely packed and parallel graphene sheets, and heating the continuous graphene fiber to form the continuous graphitic fiber at higher than 600 degrees C such that an inter-plane spacing d002 is decreased to 0.3354-0.4 nm.