METHOD OF PRODUCING DISPERSIONS OF BLOCKED POLYURETHANE PREPOLYMERS, USE THEREOF TO OBTAIN COATING AGENTS, ADHESIVE SUBSTANCES AND SEALANTS AND ELASTOMERS OBTAINED USING SAID DISPERSIONS, AS WELL AS SUBSTRATES HAVING COATINGS OBTAINED USING SAID DISPERSIONS Russian patent published in 2012 - IPC C08G18/80 C08G18/10 C08G18/32 C08G18/34 C09D175/04 C09J175/04 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing dispersions of blocked polyurethane prepolymers, use of dispersions obtained using said method to produce coating agents, adhesive substances and sealants and elastomers, said application products themselves, as well as substrates provided with coating agents. The method involves the following: I) a blocked polyurethane prepolymer is obtained first by reacting a) 100 equivalent % of at least one polyisocyanate with b) 50-90 equivalent %, in terms of isocyanate reactive groups, of a thermally split blocking agent, c) 5-45 equivalent %, in terms of isocyanate reactive groups, monohydroxycarboxylic acid as a hydrophilic agent and d) 0-25 equivalent %, in terms of isocyanate reactive groups, of polyhydroxycarboxylic acid as a hydrophilic agent and e) 0-15 equivalent %, in terms of isocyanate reactive groups, of at least one, in terms of isocyanate reactive groups, di- or polyfunctional component of a chain extender with molecular weight from 32 to 350 g/mol, where i) this takes place using (partially) water-miscible organic solvents which are inert to NCO-groups and have boiling point lower than 120°C (at 1013 mbar), ii) and they are used in such an amount that the polyurethane prepolymer contained in the reaction solution after complete conversion ranges from 70 to 98 wt %. Further, II) the polyurethane prepolymer solution obtained at step (I) is dispersed in water, where before, during or after dispersion, deprotonation of carboxylic acid groups with a base takes place at least partially, and then III) if needed, the contained organic solvent is completely removed during dispersion via distillation.

EFFECT: obtaining polyurethane dispersions which are stable during storage, endow said products of their application with good optical properties, high resistance to chemical reagents and pendulum hardness.

13 cl, 10 ex, 1 tbl