▎ 摘　　要

NOVELTY - Additive comprises a copolymer. The copolymer is made from a temperature-sensitive polymer and an amphoteric complex through transfer radical polymerization (ATRP), and reacting with functionalized graphene to obtain a graphene-containing temperature-sensitive microgel. USE - The additive is useful for aqueous lubricants (claimed). ADVANTAGE - The additive: has controllable lower critical solution temperature (LCST) value due to the temperature sensitivity; utilizes ATRP emulsion polymerization to prepare poly(ethylene glycol acrylamide) micro-gels; reacts the terminal bromine with the carboxylated graphene; connects graphene to the surface of the microgel by means of chemical bonds; increases the stability and lubricity; reduces the friction coefficient of pure water under the condition of steel friction pair from 0.5-0.11; gradually decreases the friction coefficient of aqueous lubricants, when the temperature exceeds the LCST value of the microgel; and plays the role of intelligent adjustment of lubrication. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the additive, comprising (i) adding temperature-sensitive polymers and amphoteric complex to a reaction device, introducing nitrogen into the bottle, adding crosslinking monomer, catalyst and ligand, adding water and surfactant, stirring to make it uniformly mixed, dropping the initiator, sealing the reaction for 4-6 hours under a nitrogen atmosphere to obtain a milky white micro-gel solution, (ii) adding functionalized graphene and a catalytic amount of diazabicyclo to the step (i), carrying out the reaction at 40-50° C for 3-5 hours to obtain a graphene-containing temperature-sensitive micro-gel, and (iii) dialyzing with deionized water for 5-7 days to obtain graphene-containing temperature-sensitive micro-gel.