POLYURETHANE-CONTAINING COMPOSITIONS WITH ISOCYANATE FUNCTIONALITY Russian patent published in 2022 - IPC C08G18/48 C08G18/10 C08G18/28 C08G18/42 C08G18/78 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for preparation of a reactive composition of polyisocyanate, containing a urethane group, as well as to intermediate prepolymer of polyisocyanate based on allophanate. The specified method includes mixing of intermediate prepolymer of polyisocyanate based on allophanate and an isocyanate-reactive composition containing isocyanate-reactive compounds with functionality of 1-10 and molecular weight of 100-10,000 g/mol. Intermediate prepolymer of polyisocyanate based on allophanate has NCO value in the range of 5-15 % by wt. and contains ≥ 5 wt.% and ≤ 20 wt.% of monomeric diisocyanate compounds per the total weight of prepolymer, and it is a product of reaction of at least one polyisocyanate compound and an isocyanate-reactive compound selected from monoatomic alcohol with molecular weight in the range of 32-2000 g/mol, in which the ratio of allophanate groups to urethane groups exceeds 0.05. The resulting reactive composition of polyisocyanate, containing a urethane group, contains no more than 1 wt.% of monomeric initial diisocyanate per the total weight of the specified composition of polyisocyanate, has NCO value in the range of 0.1-15 % by wt., contains urethane groups and allophanate groups, and the ratio of allophanate groups to urethane groups is from 0.05 to 100.

EFFECT: obtaining a polyurethane-containing composition with isocyanate functionality.

13 cl, 3 ex