AQUEOUS EMULSIFIER-FREE AND SOLVENT-FREE POLYURETHANE-POLYACRYLATE MIXTURE DISPERSION, PREPARATION METHOD THEREOF, USE THEREFOR, AND PREPARATION OF ELASTIC COATING HAVING HIGH ELONGATION AT BREAK AND LOW HARDNESS

摘要

PURPOSE: An aqueous emulsifier-free and solvent-free polyurethane-polyacrylate mixture dispersion, its preparation method, a coating composition containing the dispersion, a method for coating a support by using the dispersion, and a method for preparing a releasing coating material, a paint or an adhesive by using the dispersion are provided, to form a waterproof and solvent-proof coating having high elongation at break and a low hardness by using the dispersion. CONSTITUTION: The aqueous emulsifier-free and solvent-free polyurethane-polyacrylate mixture dispersion is prepared by reacting at least one kind of isocyanate component with at least one kind of component which comprises at least one kind of diol or polyol having a molecular weight of 500-6,000 and a OH value of 1.8-5, at least one kind of low molecular weight diol having a molecular weight of 62-400 and a OH value of 2 or more as a chain extender, and at least one kind of hydrophilic compound containing a nonionic and/or ionic and/or potential ionic group and having at least one NCO-reactive group, in the presence of an ethylenically unsaturated monomer inactive to an NCO group with the ratio of an NCO group to OH/NH/NH2 groups of 1:1, to obtain a hydrophilic polyurethane; dispersing the polyurethane in water; and emulsion polymerizing an ethylenically unsaturated monomer inactive to an NCO group or a mixture of an ethylenically unsaturated monomer inactive to an NCO group and a Zerevitinov-active hydrogen atom-containing an ethylenically unsaturated monomer. The produced NCO-free polyurethane is dispersed in the emulsion polymerized one.