Epoxy resin composition
Curable composition obtained by combining and mixing an epoxy resin composition comprising an epoxy resin, a monool and/or polyol and a compound comprising a carboxamide group, and a polyisocyanate composition comprising a polyisocyanate, a lithium halide and a urea compound, wherein the number of moles of lithium halide per isocyanate equivalent ranges of from 0.0001-0.04 and the number of urea+biuret equivalents per isocyanate equivalent of from 0.0001-0.4. The epoxy resin composition is claimed as well.
1. A method for increasing pot-life of a curable composition comprising combining:
a) a polyisocyanate composition comprising a polyisocyanate, a lithium halide and a urea compound having an average molecular weight of 500 to 15000 and comprising biuret groups; and
b) an epoxy resin composition comprising an epoxy resin, a monool and/or a polyol and a compound having a structure NH 2 —CO—R to form the curable composition
wherein R is selected from hydrogen, a C 1 -C 20 hydrocarbyl group, NH 2 , NR 1 R 2 , C 6 H 5 and
where R 1 and R 2 are each independently OH or a C 1 -C 10 hydrocarbyl optionally comprising 1-3 hydroxy and/or ether groups
wherein the curable composition has a number of hydroxy equivalents per epoxy equivalent of 0.02 to 100, a number of carboxamide equivalents per epoxy equivalent of 0.0005 to 1, a number of urea and biuret equivalents per isocyanate equivalent ranging from 0.0001 to 0.4 and a number of epoxy equivalents per isocyanate equivalent ranging from 0.003 to 1.
2. The method of claim 1 , wherein the urea compound is a compound obtained from a reaction of a diphenylmethane diisocyanate comprising at least 35% 4,4′-diphenylmethane diisocyanate or a carbodiimide and/or a uretonimine variant of a diphenylmethane diisocyanate comprising at least 35% 4,4′-diphenylmethane diisocyanate and an amine.
3. The method of claim 2 , wherein the amine is a polyoxyalkylene monoamine comprising oxypropylene groups in an amount of at least 50% by weight, based on the total weight of the monoamine.
4. The method of claim 1 , wherein the lithium halide is premixed with the urea compound to form a mixture and the mixture is added to the polyisocyanate.
5. The method of claim 1 , wherein the curable composition has a pot-life at ambient conditions of at least 5 hours up to 300 hours.
6. The method of claim 1 , wherein the curable composition has a pot-life at ambient conditions of at least 40 hours up to 300 hours.
7. A curable composition for making a polyisocyanurate material, the curable composition comprising: a polyisocyanate composition comprising a polyisocyanate, a urea compound having an average molecular weight of 500 to 15000 and comprising biuret groups and a lithium halide; and an epoxy resin composition comprising an epoxy resin, at least one of a monool and a polyol and a compound having a structure NH 2 —CO—R
wherein R is selected from hydrogen, a C 1 -C 20 hydrocarbyl group, NH 2 , NR 1 R 2 , C 6 H 5 and
where R 1 and R 2 are each independently OH or a C 1 -C 10 hydrocarbyl optionally comprising 1-3 hydroxy and/or ether groups
wherein the curable composition exhibits an increased pot-life as compared to a pot-life of the curable composition in the absence of the carboxamide compound.
8. The curable composition of claim 7 , wherein:
the urea compound does not comprise isocyanate-reactive groups other than urea groups;
the urea compound has an average molecular weight of 200 Daltons to 3000 Daltons;
the urea compound is a compound obtained by reacting a polyisocyanate selected from the group consisting of methylene diphenyl diisocyanate, a polyisocyanate comprising a methylene diphenyl diisocyanate, and a mixture thereof with a polyoxyalkylene monoamine comprising oxypropylene groups in an amount of at least 50% by weight calculated on the total weight of the monoamine; and
a number of urea and biuret equivalents per isocyanate equivalent is in a range of from 0.001 to 0.2 and a number of urea and biuret equivalents per mole of lithium halide is in a range of from 0.5 to 60.
9. The curable composition of claim 7 , wherein the polyisocyanate is selected from the group consisting of methylene diphenyl diisocyanate, a polyisocyanate composition comprising methylene diphenyl diisocyanate, and a mixture thereof.
10. The curable composition of claim 7 , wherein the lithium halide is present in an amount ranging from 0.00015 to 0.025 moles per isocyanate equivalent.
11. The curable composition according to claim 7 , wherein the lithium halide is lithium chloride.
12. The curable composition according to claim 7 , wherein the epoxy resin is liquid at 20° C. to 25° C.
13. A curable composition for making a polyisocyanurate material, the curable composition comprising: a polyisocyanate composition comprising a polyisocyanate, a urea compound having an average molecular weight of 500 to 15000 and comprising biuret groups and a lithium halide; and an epoxy resin composition comprising an epoxy resin, at least one of a monool and a polyol and a compound having a structure NH 2 —CO—R
wherein R is selected from hydrogen, a C 1 -C 20 hydrocarbyl group, NH 2 , NR 1 R 2 , C 6 H 5 and
where R 1 and R 2 are each independently OH or a C 1 -C 10 hydrocarbyl optionally comprising 1-3 hydroxy and/or ether groups
wherein the curable composition exhibits a pot-life of at least 5 hours up to 300 hours.
14. The curable composition of claim 13 , wherein:
the urea compound does not comprise isocyanate-reactive groups other than urea groups;
the urea compound has an average molecular weight of 200 Daltons to 3000 Daltons;
the urea compound is a compound obtained by reacting a polyisocyanate selected from the group consisting of methylene diphenyl diisocyanate, a polyisocyanate comprising a methylene diphenyl diisocyanate, and a mixture thereof with a polyoxyalkylene monoamine comprising oxypropylene groups in an amount of at least 50% by weight calculated on the total weight of the monoamine; and
a number of urea and biuret equivalents per isocyanate equivalent is in a range of from 0.001 to 0.2 and a number of urea and biuret equivalents per mole of lithium halide is in a range of from 0.5 to 60.
15. The curable composition of claim 13 , wherein a number of carboxamide equivalents per epoxy equivalent of the epoxy resin composition is in a range of from 0.0005 to 1.
16. The curable composition of claim 15 , wherein the number of carboxamide equivalents per epoxy equivalent of the epoxy resin composition is in a range of from 0.005 to 0.7.
17. The curable composition of claim 16 , wherein the number of carboxamide equivalents per epoxy equivalent of the epoxy resin composition is in a range of from 0.01 to 0.5.
18. The curable composition of claim 13 , wherein the carboxamide compound has a molecular weight of at most 499.
19. The curable composition of claim 13 , wherein a number of hydroxyl equivalents per epoxy equivalent of the epoxy resin composition is in a range of from 0.02 to 100.
20. The curable composition of claim 13 , wherein the curable composition exhibits a pot-life of at least 14 hours up to 300 hours.