Additive for reducing polyurethane foam degradation
The present disclosure relates to sulfonic acid esters for use as additives in a polyurethane formulation. The polyurethane formulation further includes a compound containing an isocyanate functional group, an active hydrogen-containing compound and a reactive amine catalyst.
1 . A polyurethane formulation comprising: (a) a sulfonic acid ester selected from (i) a compound having a formula (1)
where R 1 is a C 1 -C 18 alkyl group with one or more hydroxyl groups or a C 1 -C 18 alkoxy group with one or more hydroxyl groups and R 2 is a methyl group, a C 1 -C 18 alkyl group with one or more hydroxyl groups or a C 1 -C 18 alkoxy group with one or more hydroxyl groups; (ii) a compound having a formula (2)
where X is hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl group which may be substituted with one or more hydroxyl groups or a C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups and R 2 is a methyl group, a C 1 -C 18 alkyl group with one or more hydroxyl groups or C 1 -C 18 alkoxy group with one or more hydroxyl groups; (iii) a compound having the formula (3)
where each X is independently hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl group which may be substituted with one or more hydroxyl groups or C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups, n is an integer from 1 to 8 and R 3 is H, a C 1 -C 4 alkyl group which may be substituted with one or more hydroxyl groups or a or C 1 -C 4 alkoxy group which may be substituted with one or more hydroxyl groups; (iv) a compound having a formula (4)
where n is an integer from 1 to 5; (v) a compound having the formula (5)
where n is an integer from 1 to 3 and X is hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl group which may be substituted with one or more hydroxyl groups or C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups; and (vi) a mixture thereof; (b) a compound containing an isocyanate functional group; (c) an active hydrogen-containing compound; and (d) an isocyanate-reactive amine catalyst comprising at least one tertiary amine group and corresponding to formula (6)
wherein
R 4 and R 5 are independently a C 1 -C 4 alkyl group or R 4 and R 5 together form a cyclic 5-membered or 6-membered ring containing an O or a N heteroatom or a 7-membered bicyclic structure,
m is an integer 1 or 2, and
Y is selected from —OH, —NH 2 , —N(CH 3 ) CH 2 CH 2 OH, —NHCH 2 CH 2 CH 2 N(CH 3 ) 2 , —N(CH 3 ) CH 2 CH 2 CH 2 NH 2 , —N(CH 2 CH(CH 3 )OH) 2 , —N(CH 2 CH(CH 3 ) OH) CH 2 CH 2 CH 2 N(CH 3 ) 2 , —OCH 2 CH 2 OH, —OCH 2 CH 2 NH 2 , —OCH 2 CH 2 CH 2 NH 2 , —OCH 2 CH 2 N(CH 3 ) CH 2 CH 2 OH, and —OCH 2 CH 2 N(CH 3 ) CH 2 CH 2 CH 2 NH 2 , and
characterized in that the molar ratio of the total number of moles of the at least one tertiary amine group present in isocyanate-reactive amine catalyst (d) to the number of moles of sulfonic acid ester compound (a) in the polyurethane formulation is higher or equal than 2.
2 . The polyurethane formulation of claim 1 wherein the molar ratio of the number of moles of the at least one tertiary amine group present in isocyanate-reactive amine catalyst (d) to the number of moles of sulfonic acid ester compound (a) in the polyurethane formulation is in the range 2-5.
3 . The polyurethane formulation of claim 1 , wherein the sulfonic acid ester is a compound having the formula (2) wherein R 2 is methyl.
4 . The polyurethane formulation of claim 1 , wherein X is a lower alkyl group selected from methyl, ethyl, n-propyl, i-propyl, butyl and pentyl groups which may be substituted with one or more hydroxyl groups.
5 . The polyurethane formulation of claim 1 , wherein X is hydrogen and R 2 is methyl.
6 . The polyurethane formulation of claim 1 , wherein the sulfonic acid ester is selected from methyl p-toluene sulfonate, methyl benzene sulfonate, ethylene bis(p-toluene sulfonate) and/or 2-(2-hydroxyethoxy)ethyl 4-methylbenzenesulfonate.
7 . The polyurethane formulation of claim 1 , wherein the sulfonic acid ester is a compound having the formula (3)
8 . The polyurethane formulation of claim 7 , wherein each X is independently a C 1 -C 4 alkyl group which may be substituted with one or more hydroxyl groups or a C 1 -C 4 alkoxy group which may be substituted with one or more hydroxyl groups.
9 . The polyurethane formulation of claim 1 , wherein the isocyanate-reactive amine catalyst is a compound having the formula
10 . The polyurethane formulation according to any of foregoing claims , further comprising a blowing agent.
11 . A method for producing a polyurethane material comprising preparing a formulation by combining and/or reacting a compound containing an isocyanate functional group, an active hydrogen-containing compound and optional auxiliary components, in the presence of an isocyanate-reactive amine catalyst comprising at least one tertiary amine group according to formula (6)
wherein
R 4 and R 5 are independently a C 1 -C 4 alkyl group or R 4 and R 5 together form a cyclic 5-membered or 6-membered ring containing an O or a N heteroatom or a 7-membered bicyclic structure,
m is an integer 1 or 2, and
Y is selected from —OH, —NH 2 , —N(CH 3 ) CH 2 CH 2 OH, —NHCH 2 CH 2 CH 2 N(CH 3 ) 2 , —N(CH 3 ) CH 2 CH 2 CH 2 NH 2 , —N(CH 2 CH(CH 3 )OH) 2 , —N(CH 2 CH(CH 3 ) OH) CH 2 CH 2 CH 2 N(CH 3 ) 2 , —OCH 2 CH 2 OH, —OCH 2 CH 2 NH 2 , —OCH 2 CH 2 CH 2 NH 2 , —OCH 2 CH 2 N(CH 3 ) CH 2 CH 2 OH, and —OCH 2 CH 2 N(CH 3 ) CH 2 CH 2 CH 2 NH 2 ,
and
in the presence of a sulfonic acid ester selected from (i) a compound having a formula (1)
where R 1 is a C 1 -C 18 alkyl group with one or more hydroxyl groups or a C 1 -C 18 alkoxy group with one or more hydroxyl groups and R 2 is a methyl group, a C 1 -C 18 alkyl group with one or more hydroxyl groups or a C 1 -C 18 alkoxy group with one or more hydroxyl groups; (ii) a compound having a formula (2)
where X is hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl group which may be substituted with one or more hydroxyl groups or a C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups and R 2 is a methyl group, a C 1 -C 18 alkyl group with one or more hydroxyl groups or a C 1 -C 18 alkoxy group with one or more hydroxyl groups; (iii) a compound having the formula (3)
where each X is independently hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl group which may be substituted with one or more hydroxyl groups or a C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups, n is an integer from 1 to 8 and R 3 is H or a C 1 -C 4 alkyl group or C 1 -C 4 alkoxy group which may be substituted with one or more hydroxyl groups; (iv) a compound having a formula (4)
where n is an integer from 1 to 5; (v) a compound having the formula (5)
where n is an integer from 1 to 3 and X is hydrogen or an ortho, meta or para substituent selected from a C 1 -C 18 alkyl which may be substituted with one or more hydroxyl groups or a C 1 -C 18 alkoxy group which may be substituted with one or more hydroxyl groups; and (vi) a mixture thereof characterized in that the molar ratio of the number of moles of the at least one tertiary amine group present in isocyanate-reactive amine catalyst (d) to the number of moles of sulfonic acid ester compound (a) in the formulation is higher or equal than 2.
12 . A polyurethane material produced according to the method of claim 11 .
13 . The polyurethane material of claim 12 , wherein the polyurethane material is a rigid foam, a semi-rigid foam or a flexible foam.
14 . A polyurethane foam produced with the polyurethane formulation of claim 1 which is suitable for use in a vehicle interior or exterior parts of ships, airplanes, trucks, cars or buses.
15 . A polyurethane foam produced with the polyurethane formulation of claim 1 which is suitable for use in cars as a seat cushion, as back-foaming of a door side element, an instrument panel, as a steering wheel, a shift button, a bed liner, a dashboard or a door panel.