Water-soluble amphiphilic polymer oil-displacing agent with response to both temperature and salt, and preparation and application thereof

The invention relates to a water-soluble amphiphilic polymer oil-displacing agent with response to both temperature and salt, and preparation and application thereof, belonging to the field of preparation of oil-displacing agents for high-temperature high-salt oil reservoirs. The water-soluble amphiphilic polymer oil-displacing agent comprises acrylamide (AM), N-methyl-N-allyl-N-4-butylbenzoyl propanesulfonic acid inner salt (MABPS), diacetone acrylamide (DAAM), and azodiisobutylamidine hydrochloride (AIBA) serving as an initiator. The molar percentages of the above polymerization monomers are that AM accounts for 80%-90%, MABPS accounts for 2.5%-5% and DAAM accounts for 5%-17.5%; the mass concentration of the monomers in a solvent, namely deionized water is 20%-30%; the use amount of the initiator accounts for 0.05%-0.1% of the total mass of the monomers, and an initiation temperature is 40-50 DEG C; a copolymerization reaction is conducted by adopting a soap-free free radical polymerization method, and N2 i