Patent ID: 11869694
Assignee: TSINGHUA UNIVERSITY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A preparation method of a perfluoropolyether-based magnetic liquid, comprising:
S1, dispersing magnetic nanoparticles coated with graphene oxide into a solution of N,N-dimethylformamide to obtain solution A;
S2, dispersing a surfactant into dichloromethane, and adding triethylamine as a cosolvent to obtain solution B;
S3, mixing the solution A and the solution B uniformly, heating them under reflux and stirring them for a modification reaction; and after the modification reaction is completed, washing and drying a reaction product to obtain the modified magnetic nanoparticles coated with the graphene oxide;
S4, dispersing the modified magnetic nanoparticles coated with the graphene oxide into a base carrier liquid to prepare the perfluoropolyether-based magnetic liquid;
wherein the surfactant is a perfluoroalkylamine; and the base carrier liquid is a perfluoropolyether oil;
a mass ratio of the magnetic nanoparticles coated with the graphene oxide to the surfactant is from 20:1 to 1:1;
the modification reaction is performed at a temperature of 50 to 120° C. for a time period of 20 to 50 hours.