TWO-COMPONENT SOLVENT-FREE POLYURETHANE ADHESIVE WITH LOW CONTENT OF FREE MDI MONOMER Russian patent published in 2014 - IPC C09J175/06 C08G18/10 C08G18/36 C08G18/42 C08G18/76 

FIELD: chemistry.

SUBSTANCE: polyurethane adhesive is obtained from a polyester-polyol component A and a polyurethane prepolymer (component B) based on MDI. Component A is obtained through an esterification reaction between a dibasic alcohol and a binary acid. Component B is obtained through a reaction between an MDI monomer and a polybasic alcohol with molar ratio NCO/OH=3-5.5:1.Component B is obtained by first dehydrating the polybasic alcohol to water content of less than 0.05 wt %. The MDI monomer and a chain-terminating agent are then added. The mixture is heated to temperature 70-80°C until the hydroxyl reacts completely. A trimeric catalyst for a trimerisation reaction is added before the reaction is complete. The adhesive has a high rate of hardening, high resistance to solvents and hydrolysis, as well as excellent operational characteristics. Since components A and B in the polyurethane adhesive do not contain a solvent, they meet environmental and energy efficiency requirements. Furthermore, since the polyurethane adhesive has excellent storage stability, it is well suited for transportation and application.

EFFECT: simplicity, low production costs and low content of free MDI monomer in the obtained polyurethane adhesive.

7 cl, 3 ex