Preparation method of fluorine-containing high-molecular surfactant

The invention discloses a preparation method of a fluorine-containing high-molecular surfactant, and the preparation method comprises the following steps: enabling an initiator, methacrylic acid-N,N-ethyl dimethylamide, a chain transfer agent and 1,4-dioxane to react at 60-90 DEG C in the presence of the argon to obtain polymethylacrylic acid-N,N-ethyl dimethylamide; adding the initiator, hexafluorobutyl acrylate and 1,4-dioxane, and reacting for 2-8 hours at 65-95 DEG C in the presence of argon; precipitating in n-hexane; drying to obtain the fluorine-containing high-molecular surfactant. By adopting an RAFT polymerization technology, the prepared fluorine-containing high-molecular surfactant contains a fluorine-containing unit similar to the structure of a fluorine-containing monomer, has the characteristics of narrow molecular weight distribution, adjustable structure, low critical micelle concentration, good emulsibility, low foamability and the like, and has broad application prospect in emulsion polymerization.