Application of waterborne polyurethane

Different types of polyisocyanates can react with polyhydroxyl compounds to produce coatings with different properties to meet the needs of various application fields.Polyurethane coatings have a series of excellent properties, the most prominent advantages are wear resistance, chemical resistance, good toughness, elasticity and adhesion to the substrate, can be cured at room temperature or low temperature, so polyurethane coatings have been widely used in various fields, is considered to be the best comprehensive performance of the coating varieties

Wood paint is generally required to be beautiful and have good wear resistance and stain resistance.Waterborne polyurethane has the characteristics of wear resistance, flexibility, strong adhesion and so on. Wood paint has become an important application field of waterborne polyurethane coatings and has broad development prospects.

Automobile paint variety, electrophoresis paint, two paint, top paint, original paint, repair paint and so on.With the rapid development of the automobile industry, the requirements for automobile coating are becoming higher and higher. From the perspective of environmental protection, waterborne polyurethane is the development trend of automobile coating. Waterborne polyurethane can be used for primer, medium paint, color paint, gloss paint and repair paint of automobile surface.The waterborne polyurethane automotive coatings used at present are mainly two-component.

The loss caused by metal corrosion is very serious, especially the corrosion prevention of steel has attracted more and more attention at home and abroad.And coating anti - rust coating is one of the main methods to prevent corrosion of steel.Because of its ability to effectively overcome the solvent based coating high price, pollution shortcomings, gradually become the main development direction of coatings.

Building coatings require some properties such as lightfastness, weatherability, etc. Polyurethane dispersion coatings can fully meet the requirements by adjusting their components.Because of its excellent water resistance, durability and weather resistance, polyurethane dispersion coating has outstanding advantages for the exterior decoration of buildings. As a high-grade architectural coating, it is widely used in the economically developed United States and European countries.

⊙ Development direction ⊙

Polyurethane paint film is plump and bright, with excellent corrosion resistance, adhesion, chemical resistance and weather resistance, and has been widely used in adhesive coatings and other fields.But the single emulsion is not satisfactory in stability, self-thickening, solid content, water resistance and gloss of polyurethane resin coating.Acrylic resin has the advantages of high mechanical strength, aging resistance, anti-yellowing, good water resistance, but there are poor organic solvent resistance, poor heat resistance, low softening point, poor wear resistance and other shortcomings.

Therefore, polyurethane and polyacrylate have great complementarity in performance, and the combination of the two can get better performance of the polymer.The modification of polyurethane with acrylic resin in waterborne system is one of the important development directions in the future.