Temporary plugging agent for drilling fluid and preparation method thereof, and water-based drilling fluid and use thereof

A temporary plugging agent for drilling fluid, wherein the temporary plugging agent obtained by controlling gelatinized starch and a vinyl grafted monomer to have a polymerization reaction in an activator solution in the presence of a cross-linking agent and an initiator, wherein the vinyl grafted monomer comprises acrylic acid, acrylamide, and 2-acrylamide-2-methyl propanesulfonic acid;

• the gelatinized starch is obtained by adding starch into deionized water to have a gelatinization reaction,
• wherein based on 100 parts by weight deionized water, the starch is in 1-5 parts by weight, the vinyl grafted monomer is in 5-9 parts by weight, the initiator is in 0.5-1 parts by weight, the cross-linking agent is in 0.2-1 parts by weight, and the activator is in 0.1-3 parts by weight.