RU2021117716A - REACTION MIXTURE SUITABLE FOR THE PREPARATION OF FOAM WITH REDUCED ALDEHYDE EMISSIONS - Google Patents

Claims (26)

1. A reaction mixture for the preparation of polyurethane foam, where the mixture can be obtained by reacting a polyfunctional isocyanate with an isocyanate-reactive compound in the presence of an absorbent and at least one catalyst, where the absorbent contains a compound of the following formula (I):

(I) where R1 and R2 are independently selected from -OR3, R4 or from the group consisting of a hydroxy group, an ether group, a halogen, a carbonyl group, a carboxyl group, an isocyanate, a nitro group and/or an amine group, R ₃ and R ₄ are independently selected from a combination of linear, branched, saturated, unsaturated, cyclic and/or non-cyclic carbon chains, aliphatic hydrocarbons, araliphatic hydrocarbons, aromatic hydrocarbons and mixtures thereof, optionally interrupted by one or more oxygen atoms, nitrogen atoms and/or sulfur atoms, and optionally containing any functional group selected from a hydroxy group, an ether group, a halogen, a carbonyl group, a carboxyl group, an isocyanate, a nitro group and/or an amine group, R ₁ and R ₂ can be connected to each other, essentially forming at least one ring structure, preferably a structure of at least 2 rings. 2. The reaction mixture according to claim 1, wherein said scavenger advantageously comprises said compound of formula (I) when added to the reaction mixture in an aqueous solution state. 3. The reaction mixture according to claim 1 or 2, where the specified scavenger is added to the reaction mixture at a temperature in the range from 18 to 45°C. 4. The reaction mixture according to any one of the preceding paragraphs, wherein R1 is -OR3. 5. The reaction mixture according to any one of the preceding claims, wherein said scavenger consists of at least 90% by weight of said compound of formula (I), preferably at least 95% by weight, more preferably about 99% by weight .% relative to the total mass of the specified absorber. 6. The reaction mixture according to any of the preceding claims, wherein R ₁ and R ₂ are bonded to each other to form a 5-12 membered structure and contain unsaturations, aromatic rings and/or heteroatoms, preferably a structure of at least 2 rings. 7. The reaction mixture according to any one of the preceding claims, wherein said scavenger has a molecular weight of at most 3000 g/mol, preferably below 1500 g/mol, more preferably below 500 g/mol. 8. The reaction mixture according to any one of the preceding paragraphs, containing a foaming agent. 9. The reaction mixture according to any one of the preceding claims, wherein the polyfunctional isocyanate is selected from polymeric methylene diphenyl diisocyanate, a mixture of methylene diphenyl diisocyanate isomers, or a mixture thereof. 10. The reaction mixture according to any one of the preceding claims, wherein the isocyanate-reactive compound is a polyfunctional polyol or a polyfunctional amine, preferably a polyfunctional polyol, and more preferably a polyether polyol. 11. A method for the preparation of polyurethane foam, including the following steps: a. obtaining a reaction mixture containing a polyfunctional isocyanate and an isocyanate-reactive compound; b. adding an absorbent and at least one catalyst to said reaction mixture, optionally together with at least one blowing agent; where the specified absorbent contains a compound of the following formula (I):

(I) where R1 and R2 are independently selected from -OR3, R4, or from the group consisting of a hydroxy group, an ether group, a halogen, a carbonyl group, a carboxyl group, an isocyanate, a nitro group and/or an amine group, R ₃ and R ₄ are independently selected from a combination of linear, branched, saturated, unsaturated, cyclic and/or non-cyclic carbon chains, aliphatic hydrocarbons, araliphatic hydrocarbons, aromatic hydrocarbons and mixtures thereof, optionally interrupted by one or more oxygen atoms, nitrogen atoms and/or sulfur atoms, and optionally containing any functional group selected from a hydroxy group, an ether group, a halogen, a carbonyl group, a carboxyl group, an isocyanate, a nitro group and/or an amine group, R ₁ and R ₂ may be connected to each other, essentially forming at least one ring structure, preferably a structure of at least 2 rings; c. curing said reaction mixture, which contains at least a reaction product of said polyisocyanate and said isocyanate-reactive compound, in the presence of said scavenger and said at least one catalyst, resulting in the formation of a polyurethane foam. 12. The method of claim 11, wherein said scavenger advantageously comprises said compound of formula (I) when added to the reaction mixture in an aqueous solution state. 13. The method according to any one of claims 11 or 12, wherein said reaction mixture has an NCO value ranging from about 0.6 to about 1.5, preferably from about 0.8 to about 1.3. 14. A method according to any one of claims 11 or 12, wherein the NCO of the reaction mixture is in the range of from about 1.05 to about 10, preferably from about 1.05 to about 4.