The hydroxy acrylic resin has excellent weather resistance and gloss and color retention. The two-component acrylic polyurethane coating made of aliphatic isocyanate as a curing agent is widely used in the automotive and aerospace industries, and is an excellent outdoor coating. In the past 20 years, China has also done a lot of work on acrylic polyurethane coatings, and has begun to use it for wind power blade protective coatings 

    Coatings made of hydroxy acrylic resin tend to have excellent weatherability and hardness, but are not ideal in terms of flexibility, impact resistance and abrasion resistance [29]. Currently, polyester resins are generally used for modification. Zhou Shujun used E-10 (glycidyl glyceryl carbonate) synthetic polyester prepolymer modified acrylic resin and pure acrylic resin, and prepared into a topcoat respectively. The performance comparison results showed that the surface made of polyester modified acrylic resin The flexibility and impact resistance of the paint are significantly increased, and the hardness of the paint film can be well balanced. Li Rujian et al. used a combination of acrylic resin and polyester to prepare a coating that can be applied to wind turbine blades and compared it with an imported brand sample. It is found that with the increase of the amount of acrylic resin, the weather resistance of the coating film becomes better; and when the amount of polyester polyol is increased, the impact resistance, adhesion and abrasion resistance of the product are improved. The wear resistance and adhesion of the developed products are better than that of an imported product, and the weather resistance is equivalent to that of an imported product.

    The polyester modified acrylic polyurethane system can significantly improve the flexibility, impact resistance and wear resistance of the paint film, but it will reduce the weather resistance and low temperature elongation of the paint film. Sun Wei et al. compared the stone-resistance performance of topcoats made of acrylic polyurethane, polyester modified acrylic polyurethane, polyester polyol polyurethane and polycarbonate polyurethane, and found the abrasion resistance of polyester modified acrylic polyurethane topcoat. Preferably, acrylic polyurethane topcoats have the worst abrasion resistance, but their stone-resisting properties are poor, while the abrasion resistance of polycarbonate polyurethane topcoats and polyester polyol polyurethane topcoats is better than polyester modification. Acrylic polyurethane topcoats are a bit worse, but these two topcoats have the best stone resistance.

    The polyester modified acrylic polyurethane topcoat is simple in preparation, convenient in construction, and has excellent comprehensive performance of the paint film. It is widely used in the field of domestic wind power blades, but it has better performance than the polyurethane of the polyester polyol system. Abrasion resistance, but poor stone resistance, not suitable for the leading edge protection of the blade, so the polyester modified acrylic polyurethane system is used as the blade topcoat, and the polyurethane with the polyester polyol system is used as the blade leading edge repairing surface. Paint can bring better protection to wind turbine blades.