▎ 摘　　要

NOVELTY - A lubricating oil composition used for improving low-temperature fluidity, comprises 0.01-15 wt.% graphene and 85-99.99 wt.% ultra-high viscosity poly-alpha-olefin. The graphene is single-layer or multi-layer exfoliated and dispersed graphene oxide, redox graphene, fluorinated graphene, fluorinated graphene oxide or fluorinated redox graphene. The ultra-high viscosity poly-alpha-olefin is ultra-high viscosity poly-alpha-olefin metallocene poly-alpha-olefin (mPAO) obtained by metallocene catalytic polymerization. USE - The lubricating oil composition is used as viscosity index improver for improving low-temperature fluidity (claimed) and in extremely cold area - 58degrees Celsius. ADVANTAGE - The product greatly improves viscosity index of lubricating oil, gives oil more excellent low temperature fluidity, and ensures normal operation of mechanical equipment in extremely cold area. The blended 75W-90 automotive gear oil with kinematic viscosity of 17.5 mm2/s at 100degrees Celsius has Brookfield viscosity of 20.7% and 24.7% of GL5 standard requirements at - 40degrees Celsius. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method for preparing lubricating oil composition comprising adding graphene to ultra-high viscosity poly-alpha-olefin mPAO and performing ultrasonic dispersion at 30-65degrees Celsius; and (2) an application of lubricating oil composition for preparing lubricating oil product comprising 55-90 wt.% base oil, 3-18 wt.% lubricating oil composition, 5-15 wt.% synthetic ester, 0.5-12 wt.% composite additive, 0.01-0.1 wt.% antifoaming agent and 0.01-0.15 wt.% antioxidant. Modulation method of lubricating oil product involves putting base oil into reaction kettle, heating to 50-80degrees Celsius, orderly adding lubricating oil composition, synthetic ester, composite additive, antifoaming agent and antioxidant to reaction kettle, stirring for 40-60 minutes at rotating speed of 300-400 revolutions/minute, transferring material in reaction kettle to storage tank and standing for 40-60 minutes.