METHOD OF PRODUCING ISOCYANATE PREPOLYMERS Russian patent published in 2013 - IPC C08G18/12 C08L75/00 C08K13/02 C09D175/00 C09K3/10 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isocyanate prepolymers containing 10-21 wt % terminal NCO groups, intended for use as a polymer base of polyurethane, polyurea and polyurea-urethane sprayed anticorrosion coatings and sealing compounds. The method is based on treating oligooxypropylene triol with molecular weight of 4500-6000 units at temperature 30-85°C with diphenyl methane polyisocyanate in the presence of intramolecular urethane-formation reaction inhibitor additives, the inhibitor used being distilled tall oil, taken in amount of 0.5-1.2 wt % of the weight of reacting components, with molar ratio of the oligooxypropylene triol to diphenyl methane polyisocyanate which provides content of NCO groups of 10-21 wt % in the finished prepolymer.

EFFECT: synthesis of urethane prepolymers with high content of NCO groups, which retain their viscosity properties at a level which meets process requirements for a long period of time.

1 dwg, 4 tbl, 6 ex