Hyperbranched polyester modified acrylic resin and preparation method thereof

The invention relates to hyperbranched polyester modified acrylic resin and a preparation method thereof. Firstly, a By-type polyhydroxylated compound is taken as nuclear molecules (wherein B represents hydroxyl, and the degree of functionality y of B is larger than of equal to 2), ABx-type polyhydroxy acid is taken as divergence molecules (wherein A represents carboxyl, B represents hydroxyl and x represents the degree of functionality of hydroxyl and is larger than or equal to 2), a polyester-type hyperbranched polymer with hydroxyl at the terminal is obtained through a vacuum fusion polycondensation method, and esterification reaction is performed on prepared hyperbranched polyester and acrylic resin with carboxyl in the presence of a water-carrying agent to obtain hyperbranched polyester modified acrylic resin. Acrylate with hyperbranched polyester introduced enriches a great amount of hydroxyl, and is taken as a cross-linking group to greatly reduce the curing time of a coating film; and at the same time