Epoxy resin and 4,4′-diaminobenzanilide powder
View Patent ↗Epoxy resin compositions that include an epoxy resin component and a curative powder comprising particles of 4,4′-diaminobenzanilide (DABA) wherein the size of the DABA particles is less than 100 microns and wherein the median particle size is below 20 microns.
1. An uncured epoxy resin composition comprising:
an epoxy resin component; and
a curative powder comprising particles of 4,4′-diaminobenzanilide wherein the size of said particles is less than 100 microns and wherein the median particle size is below 20 microns.
2. An uncured epoxy resin composition according to claim 1 wherein said the median particle size is between 10 microns and 20 microns.
3. An uncured epoxy resin composition according to claim 1 wherein said epoxy resin component consists essentially of a trifunctional epoxy.
4. An uncured epoxy resin composition according to claim 1 which further includes a fibrous support structure.
5. An uncured epoxy resin composition according to claim 1 wherein the stoichiometric ratio of said epoxy component to said 4,4′-diamino benzanilide is between 1.0 to 1.0 and 1.0 to 0.7.
6. An uncured epoxy resin composition according to claim 5 wherein the stoichiometric ratio of said epoxy component and said 4,4′-diamino benzanilide is about 1.0 to 0.85.
7. An uncured epoxy resin composition according to claim 1 wherein at least 70 percent of the particles in said curative powder have a particle size of below 50 microns.
8. A cured epoxy resin composition according to claim 1 wherein said epoxy resin component has been cured.
9. A cured epoxy resin composition according to claim 4 wherein said epoxy resin component has been cured.
10. A cured epoxy resin composition according to claim 8 which has a flexural strength of at least 25 ksi and a strain to failure of at least 4.0 percent.
11. A method for making an uncured epoxy resin composition comprising the steps of:
providing an epoxy resin component;
providing a curative powder comprising particles of 4,4′-diaminobenzanilide wherein the size of said particles is less than 100 microns and wherein the median particle size is below 20 microns;
mixing together said epoxy resin component and said curative powder to provide said uncured epoxy resin composition.
12. A method for making an uncured epoxy resin composition according to claim 11 wherein said median particle size is between 10 microns and 20 microns.
13. A method for making an uncured epoxy resin composition according to claim 11 wherein said epoxy resin component consists essentially of a trifunctional epoxy.
14. A method for making an uncured epoxy resin composition according to claim 11 which further includes the step of combining said uncured epoxy resin composition with a fibrous support structure.
15. A method for making an uncured epoxy resin composition according to claim 11 wherein the stoichiometric ratio of said epoxy component to said 4,4′-diamino benzanilide is between 1.0 to 1.0 and 1.0 to 0.7.
16. A method for making an uncured epoxy resin composition according to claim 15 wherein the stoichiometric ratio of said epoxy component and said 4,4′-diamino benzanilide is about 1.0 to 0.85.
17. A method for making an uncured epoxy resin composition according to claim 11 wherein at least 70 percent of the particles in said curative powder have a particle size of below 50 microns.
18. A method for making a cured epoxy resin composition according to claim 11 wherein said method comprises the additional step of curing said epoxy resin component.
19. A method for making a cured epoxy resin composition according to claim 14 wherein said method comprises the additional step of curing said epoxy resin component.
20. A method for making a cured epoxy resin composition according to claim 18 wherein said cured epoxy resin composition has a flexural strength of at least 25 ksi and a strain to failure of at least 4.0 percent.