Water-based modified polyester resin as well as preparation method and application thereof

The invention relates to the technical field of preparation of pre-coated coiled material coatings. The preparation method comprises the following steps: firstly, designing a basic resin which is prepared by reacting sodium sulfonate, neopentyl glycol, methylpropanediol, 2-butyl-2-ethyl-1, 3-propylene glycol, dimethylolpropionic acid, trimethylolpropane, a catalyst, monoacid, adipic acid, isophthalic acid, maleic anhydride, itaconic acid and the like; the preparation method comprises the following steps: reacting basic resin, styrene, methyl methacrylate, lauryl ester, methacrylic acid, an initiator and the like to prepare water-based modified polyester resin; the water-based modified polyester resin, the water-based dispersing agent, the anti-settling agent, the water-based defoaming agent, the cosolvent, the amino resin, the water-based flatting agent, the acid catalyst, the water-based anti-explosion agent and the like are stirred, mixed and ground, then the viscosity is adjusted to 55-85 s, the pre-coatin