ADHESIVE SYSTEM FOR LIGNOCELLULOSE SUBSTRATES HAVING HIGH LEVELS OF EXTRACTIVE SUBSTANCES Russian patent published in 2019 - IPC C08G18/10 C09J175/04 C09D171/02 C09J5/02 B32B21/00 B32B21/13 B32B7/12 B27N3/00 

FIELD: chemistry.

SUBSTANCE: present invention relates to an adhesive system for producing lignocellulose composites comprising: (a) a primer composition having pH in range of 6 to 8; and (b) the polyurethane adhesive composition. Said priming composition contains: (i) from 1 to 100 wt. % a composition of at least one compound having a hydroxyl number less than or equal to 30 mg KOH/g and selected from a group consisting of polyalkylene glycols, monoethers of polyalkylene glycols and polyetherethylene glycol diester; (ii) 0–99 wt. % solvent composition; and (iii) 0–5 wt. % a surfactant composition selected from a group consisting of water-soluble surfactants, water-emulsifiable surfactants and mixtures thereof. Said polyurethane adhesive composition is a moisture-curable one-component polyurethane adhesive composition and contains: prepolymer having free NCO groups, said prepolymer being obtained from at least one component A containing a compound which reacts to isocyanates, and, at least, one component B containing isocyanate; from 0 to 40 wt. %, preferably from 0.1 to 30 wt. %. filler; from 0 to 20 wt. % conventional additives and excipients; and from 0 to 20 wt. % activator; and wherein said prepolymer having free NCO groups is characterized by (i) an NCO content of from 5 to 30 wt. %, preferably from 10 to 25 wt. %, relative to the prepolymer; (ii) functionality from 2.2 to 3, preferably, from 2.4 to 2.9. Also disclosed is a method of producing a glued lignocellulose article using said adhesive system and an adhesive lignocellulose article obtained using said method.

EFFECT: technical result is the development of an adhesive system, which when applied on wood or lignocellulose substrates containing high levels of water-soluble extractive substances, provides improved durability and ideal strength of adhesion of the system to the substrate.

18 cl, 4 tbl, 4 ex