Encapsulated catalyst for aerospace grade resin systems
Methods and compositions, and components comprising the compositions, are disclosed relating to improved resin-based adhesives comprising encapsulating at least a catalyst compound. Further methods and compositions are disclosed relating to encapsulated catalysts in uncured resin-based adhesives, said encapsulated catalysts configured to release the catalyst compound and cure the uncured resin-based adhesive on-demand.
1. A method for adhering layed up resin-based composite materials comprising the steps of:
applying a first resin-based composite material to a second resin-based composite material, said first resin-based composite material and second resin-based composite material comprising an uncured resin-based adhesive compound, said uncured resin-based adhesive compound comprising an amount of encapsulated catalyst, said encapsulated catalyst encapsulated within a shell, said encapsulated catalyst comprising a predetermined volume of inert gas within the shell;
exposing the encapsulated catalyst encapsulated within the shell to a predetermined temperature and predetermined pressure to rupture the shell;
releasing the encapsulated catalyst and inert gas from the shell to the first resin-based composite material and the second resin-based composite material;
substantially dissolving the released inert gas into the first resin-based composite material and the second resin-based composite material;
laying up the first resin-based composite material to the second resin-based composite material; and
curing the first resin-based composite material and second resin-based composite material.
2. The method of claim 1 , wherein the encapsulated catalyst is exposed to a temperature ranging from about 70° F. to about 110° F.
3. The method of claim 1 , wherein the encapsulated catalyst is exposed to a pressure ranging from about 30 psi to about 100 psi.
4. The method of claim 1 , wherein the shell comprises a shell diameter ranging from about 0.05 microns to about 0.5 microns.
5. The method of claim 1 , wherein the encapsulated catalyst is in a solid state or in a liquid state at room temperature.
6. The method of claim 5 , wherein the shell comprises a shell diameter ranging from about 0.5 microns to about 2.0 microns.
7. The method of claim 1 , wherein the shell has a melting point ranging from about 100° F. to about 300° F.
8. The method of claim 1 , wherein the uncured resin-based adhesive compound comprises an epoxy resin-based compound.
9. The method of claim 1 , wherein the encapsulated catalyst is a compound comprising tris-(dimethylaminomethyl) phenol, nonyl phenol, benzyldimethylamine, triethanolamine boron trichloride methyl amine, boron trichloride ethylamine and homologues, boron trifluoride methyl amine, boron trifluoride ethylamine and homologues, boron trifluoride dimethylamine, boron trifluoride diethylamine and homologues, boron trifluoride trimethylamine, boron trifluoride triethylamine and homologues, boron trifluoride piperadine, boron trifluoride hexylamine, 4,4′ methylene bis(phenyl dimethyl urea), 1,1′-(4 methyl-m-phenylene) bis(3,3 dimethyl urea), isophthalic dihydrazide, 2-methylimidazole, 2-ethyl-4-methylimidazole, 4,4′-diaminodiphenyl sulfone, dicyandiamide-containing compounds, imidazole-containing compounds or combinations thereof.
10. The method of claim 1 , wherein the uncured resin-based adhesive compound is an epoxy resin-based compound comprising diglycidyl ethers of bisphenol A; diglycidyl ethers of bisphenol F; diglycidyl dihydroxy naphthalene, N,N,N′,N′-tetraglycidyl- 4,4′-diaminophenylmethane; p-amino phenol triglycidyl ether; epoxy phenol novolac resins; epoxy cresol novolac resins; 1,3,5-triglycidyl isocyanurate; tris(2,3-epoxypropyl)isocyanurate; glycerol diglycidyl ether; trimethylolpropane triglycidyl ether, or combinations thereof.
11. The method of claim 1 , wherein the encapsulated catalyst comprises at least one amine.
12. The method of claim 11 , wherein said amine comprises aliphatic primary amines, aliphatic secondary amines, aromatic amines, and combinations thereof.
13. The method of claim 1 , wherein, when the encapsulated catalyst is in a liquid state, the catalyst comprises tris-(dimethylaminomethyl) phenol, nonyl phenol, benzyldimethylamine, triethanolamine, or combinations thereof.
14. The method of claim 1 , wherein the uncured resin-based adhesive compound comprises an acrylate resin-based compound.
15. The method of claim 14 , wherein the acrylate resin-based compound comprises a monoacrylate, a diacrylate, a triacrylate, a tetraacrylate, a pentaacrylate, or combinations thereof.