Aqueous polyurethane acrylate dispersion, preparation method thereof, and coating material with self repairing function

Abstract

The invention relates to the technical field of coating materials, and provides a preparation method of an aqueous polyurethane acrylate dispersion. The preparation method comprises following steps: reacting diisocyanate with polyester polyol or polyether polyol to obtain a polyurethane prepolymer; mixing the polyurethane prepolymer with a viscosity reduced solvent, a hydrophilic chain extender, and a chain extender containing allyl thioether groups, carrying out reactions to obtain a first mixed solution; mixing the first mixed solution with hydroxyl containing acrylate monomers, carrying outreactions to obtain a double bond terminated polyurethane prepolymer; adding water into the double bond terminated polyurethane prepolymer, carrying out emulsification, removing the solvent, performing dilution until the solid content reaches 20 to 30% to obtain a second mixed solution; mixing the second mixed solution with acrylate monomers, carrying out emulsification, mixing the emulsion withan initiator solution, and carrying out reactions. The aqueous polyurethane acrylate dispersion is prepared by the method mentioned above. A coating material with a self repairing function comprises the aqueous polyurethane acrylate dispersion and a photo initiator. The coating material has a good self repairing performance under the irradiation of UV rays.

Description

technical field

[0001] The invention relates to the technical field of finishing materials, in particular to a water-based polyurethane acrylate dispersion, a preparation method thereof, and a finishing material with self-repairing properties. Background technique

[0002] Polyurethane has excellent mechanical properties, excellent cold resistance, wear resistance and elasticity, but its high temperature resistance, weather resistance and hydrolysis resistance are poor, and polyacrylate has good gloss, water resistance and outdoor aging resistance. characteristics, but high hardness, poor adhesion, and poor flexibility. Utilizing the complementary properties of polyurethane (PU) and polyacrylate (PA), the polyurethane resin can be modified by acrylate to obtain a polyurethane-acrylate composite material with excellent performance. Waterborne polyurethane acrylate is called the fourth generation of waterborne Polyurethane.

[0003] Polyurethane-acrylate composite materials ...

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