▎ 摘　　要

NOVELTY - Functional heating fluid material comprises a carbon family nanomaterial mixture comprising carboxylated graphene and carboxylated multi-walled carbon nanotubes, where the carbon family nanomaterial mixture is chemically modified by a long-chain alkyl quaternary ammonium salt. USE - Functional heating fluid material. ADVANTAGE - The material has high thermal conductivity and excellent suspension stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the fluid material, involving (a) adding the above-mentioned components to water, and uniformly dispersing by ultrasonically processing, (b) adding the long-chain alkyl quaternary ammonium salt in a weight ratio of (8-12):1, and reacting at 80-95 degrees C for 1-6 hours, (b) washing with anhydrous methanol and water, and drying at 60-80 degrees C to obtain a long-chain alkyl quaternary ammonium salt chemically modified carbon family nanomaterial mixture, and (c) uniformly mixing the long-chain alkyl quaternary ammonium salt chemically modified carbon-family nanomaterial mixture with free long-chain alkyl quaternary ammonium salt, polyethyleneimine and base fluid to obtain the fluid material.