Hydrophilic polystyrene microspheres and preparation method thereof

The invention provides a hydrophilic polystyrene microsphere and a preparation method thereof. The hydrophilic polystyrene microsphere comprises a polystyrene microsphere and an amphiphilic polymer coating layer which is physically adsorbed on the surface of the polystyrene microsphere, wherein the amphiphilic polymer coating layer is formed by crosslinking polyvinyl alcohol grafted and modified by an amphiphilic epoxy compound; wherein the amphiphilic epoxy compound contains a phenyl group. By applying the technical scheme of the invention, the hydrophilic polystyrene microsphere introduces polyvinyl alcohol (namely PVA) into a hydrophobic structural unit through a chemical modification method, and then physical adsorption is carried out through interaction between the modified PVA with increased hydrophobic points and hydrophobic groups such as benzene rings or residual double bonds on the surface of the polystyrene microsphere; then, a proper cross-linking agent is selected for cross-linking to form a hydr