▎ 摘　　要

NOVELTY - Preparing graphene/polypyrrole nanoparticles having negative dielectric constant comprises e.g. (i) weighing protonic acid, oxidant and graphene, adding water, and ultrasonically dispersing to fully disperse oxidant, protonic acid and graphene in water, (ii) ultrasonically dispersing pyrrole (Py) in 60 ml water to obtain Py dispersion, and ultrasonically dispersing Py dispersion in ice water mixture, (iii) placing dispersing liquid A in mixture of ice and water in crystallizing dish, and placing the crystallizing dish on magnetic stirrer, when the temperature of the dispersion A is lower than 10 degrees C, dropwise adding dispersion B while stirring, controlling the molar ratio of protonic acid, oxidant and pyrrole during the reaction, and reacting in ice water bath, allowing to stand, and (iv) suction filtering the reaction solution after allowing to stand in sand core funnel, washing until the supernatant is colorless and transparent, obtaining graphene-doped polypyrrole (PPy) and drying. USE - The nanoparticle is useful for preparing nanocomposite electromagnetic metamaterials. ADVANTAGE - The nanoparticle: has negative value compared with the dielectric constant epsilon of the graphene/polypyrrole synthesized and uniform particle size; helps to expand the application of metamaterials in the fields of stealth, micro antennas and electronic components; these are in the form of powder. DETAILED DESCRIPTION - Preparing graphene/polypyrrole nanoparticles having negative dielectric constant comprises (i) weighing 0.1 mol protonic acid, 0.06 mol oxidant and 10-70% graphene, and adding 300 ml water, and ultrasonically dispersing at 320 W power for 50 minutes to fully disperse oxidant, protonic acid and graphene in water, (ii) ultrasonically dispersing 0.08 mol pyrrole (Py) in 60 ml water to obtain Py dispersion, and ultrasonically dispersing Py dispersion in an ice water mixture under ultrasonic power of 320 W for 50 minutes, (iii) placing dispersing liquid A in mixture of ice and water in crystallizing dish, and placing the crystallizing dish on magnetic stirrer, stirring at speed of 800-1000 revolutions per minute (rpm), when the temperature of the dispersion A is lower than 10 degrees C, dropwise adding 60 ml dispersion B while stirring for 5-10 minutes, controlling the molar ratio of protonic acid, oxidant and pyrrole to be 5:3:4 during the reaction, and reacting in an ice water bath for 6-12 hours, and allowing to stand for 24-48 hours, and (iv) suction filtering the reaction solution after allowing to stand in sand core funnel, washing with deionized water and ethanol until the supernatant is colorless and transparent, obtaining graphene-doped polypyrrole (PPy) and drying in blast oven at 80 degrees C for 6 hours.