Reaction mixture suitable for manufacturing of foam with reduced aldehyde emission
Disclosed is a reaction mixture for the manufacturing of a polyurethane foam, which mixture can be obtained by reacting a polyfunctional isocyanate with an isocyanate-reactive compound, in the presence of a scavenger and at least one catalyst; and curing such reaction mixture enables providing a foam with reduced aldehyde emissions particularly useful in means of transport, such as interior part of cars.
1. A reaction mixture for the manufacturing of a polyurethane foam, the reaction mixture comprising a polyfunctional isocyanate, an isocyanate-reactive compound, a scavenger and at least one catalyst, wherein the scavenger comprises a compound of the following formula (I):
wherein,
R 1 and R 2 are independently of one another selected from —OR 3 , R 4 or from the group consisting of hydroxy, ether, halogen, carbonyl, carboxyl, isocyanate, nitro and/or amine groups,
R 3 and R 4 are independently of one another selected from a combination of saturated linear, saturated branched, cyclic and/or saturated non-cyclic carbon chains, saturated aliphatic hydrocarbons, araliphatic hydrocarbons, aromatic hydrocarbons and mixtures thereof, optionally interrupted by one or more oxygen atoms, nitrogen atoms and/or sulphur atoms, and optionally comprising any functional group selected from hydroxy, ether, halogen, carboxyl, isocyanate, nitro and/or amine groups,
R 1 and R 2 may be linked to each other essentially forming at least one ring structure.
2. The reaction mixture according to claim 1 , wherein said compound with formula (I) is in an aqueous condition when added to the reaction mixture.
3. The reaction mixture according to claim 1 , wherein said scavenger is added to the reaction mixture at a temperature ranging from 18 to 45° C.
4. The reaction mixture according to claim 1 , wherein R 1 is —OR 3 .
5. The reaction mixture according to claim 1 , wherein said scavenger is made of at least 90 wt % of said compound of formula (I) based on the total weight of said scavenger.
6. The reaction mixture according to claim 1 , wherein R 1 and R 2 are linked to each other to form a 5 to 12 membered ring structure and comprise unsaturations, aromatic rings and/or heteroatoms.
7. The reaction mixture according to claim 1 , wherein said scavenger has a molecular weight of at most 3000 g/mol.
8. The reaction mixture according to claim 1 , wherein the reaction mixture further comprises a blowing agent.
9. The reaction mixture according to claim 1 , wherein the polyfunctional isocyanate is selected from a polymeric methylene diphenyl diisocyanate, a methylene diphenyl diisocyanate isomer mixture, or a mixtures thereof.
10. The reaction mixture according to claim 1 , wherein the isocyanate-reactive compound is a polyfunctional polyol or a polyfunctional amine.
11. A process for the manufacturing of a polyurethane foam, comprising the following steps:
(a) providing a reaction mixture comprising a polyfunctional isocyanate and an isocyanate-reactive compound;
(b) adding a scavenger and at least one catalyst to said reaction mixture, then adding at least one blowing agent to the reaction mixture;
wherein said scavenger comprises a compound of the following formula (I):
wherein,
R 1 and R 2 are independently of one another selected from —OR 3 , R 4 , or from the group consisting of hydroxy, ether, halogen, carbonyl, carboxyl, isocyanate, nitro and/or amine groups,
R 3 and R 4 are independently of one another selected from a combination of saturated linear, saturated branched, cyclic and/or saturated non-cyclic carbon chains, saturated aliphatic hydrocarbons, araliphatic hydrocarbons, aromatic hydrocarbons and mixtures thereof, optionally interrupted by one or more oxygen atoms, nitrogen atoms and/or sulphur atoms, and optionally comprising any functional group selected from hydroxy, ether, halogen, carboxyl, isocyanate, nitro and/or amine groups,
R 1 and R 2 may be linked to each other essentially forming at least one ring structure; and
(c) curing said reaction mixture, which comprises at least the reaction product of said polyisocyanate and said isocyanate-reactive compound in the presence of said scavenger and said at least one catalyst, leading to the formation of a polyurethane foam.
12. The process according to claim 11 , wherein said compound with formula (I) is in an aqueous condition when added to the reaction mixture.
13. The process according to claim 11 , wherein, said reaction mixture has an NCO index in the range of from about 0.6 to about 1.5.
14. The process according to claim 11 , wherein, the NCO index of the reaction mixture is in the range of from about 1.05 to about 10.