Curable compositions
View Patent ↗Curable compositions, such as benzoxazine-based ones, are useful in applications within the aerospace industry, such as for example as a heat curable composition for use as a matrix resin or an adhesive, and form the basis of the present invention.
1. A prepreg comprising a layer of fibers infused with a heat curable composition comprising:
(a) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alky (when o is 1), alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2) , and R 1 is alkyl; and
(b) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups.
2. The prepreg of claim 1 , wherein the fiber layer is made from unidirectional fibers.
3. The prepreg of claim 1 , wherein the fiber layer is made from woven fibers.
4. The prepreg of claim 1 , wherein the fiber is selected from the group consisting of carbon, glass, aramid, boron, polyalkylene, quartz, polybenzimidazole, polyetheretherketone, polyphenylene sulfide, poly p-phenylene benzobisoaxazole, silicon carbide, phenolformaldehyde, phthalate and napthenoate.
5. The prepreg of claim 4 , wherein the glass is a member selected from the group consisting of S glass, S2 glass, E glass, R glass, A glass, AR glass, C glass, D glass, ECR glass, glass filament, staple glass, T glass and zirconium oxide glass.
6. The prepreg of claim 4 , wherein the carbon is a member selected from the group consisting of polyacrylonitrile, pitch and acrylic.
7. Cured reaction products of the prepreg of claim 1 .
8. A prepreg made by a process for producing a prepreg, steps of which comprise:
(a) providing a layer of fibers;
(b) providing a heat curable composition comprising:
(i) a benzoxazine component comprising
wherein o is 1-4, X s member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1), alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(ii) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene, co-polymer having secondary amine terminal groups; and
(c) joining the heat curable composition and the layer of fibers to form a prepreg assembly, and exposing the resulting prepreg assembly to elevated temperature and pressure conditions sufficient to infuse the layer of fibers with the heat curable composition to form a prepreg.
9. A prepreg made by a process for producing a prepreg, steps of which comprise:
(a) providing a layer of fibers;
(b) providing a heat curable composition comprising:
(i) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1) alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(ii) about 5 Weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups in liquid form;
(c) passing the layer of fibers through the liquid heat curable composition to infuse the layer of fibers with the heat curable composition; and
(d) removing excess heat curable composition from the prepeg assembly.
10. Cured reaction product of the prepreg of claim 8 .
11. Cured reaction product of the prepreg of claim 9 .
12. A towpreg comprising:
(a) a bundle of fibers infused with a heat curable composition comprising:
(i) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1), alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(ii) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups.
13. The towpreg of claim 12 , wherein the fibers are selected from the group consisting of carbon, glass, aramid, boron, polyalkylene, quartz, polybenzimidazole, polyetheretherketone, polyphenylene sulfide, poly p-phenylene benzobisoaxazole, silicon carbide, phenolformaldehyde, phthalate and napthenoate.
14. The towpreg of claim 13 , wherein the glass is a member selected from the group consisting of S2 glass, E glass, R glass, R glass, A glass, AR glass, C glass, D glass, ECR glass, glass filament, staple glass, T glass and zirconium oxide glass.
15. The towpreg of claim 13 , wherein the carbon is a member selected from the group consisting of polyacrylonitrile, pitch and acrylic.
16. Cured reaction products of the towpreg of claim 12 .
17. A towpreg made by a process for producing a towpreg, steps of which comprise:
(a) providing a bundle of fibers;
(b) providing a heat curable composition comprising:
(i) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1), alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(ii) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups; and
(c) joining the heat curable composition and the bundle of fibers to form a towpreg assembly, and exposing the resulting towpreg assembly to elevated temperature and pressure conditions sufficient to impregnate the bundle of fibers with the heat curable composition to form a towpreg.
18. A towpreg made by a process for producing a towpreg, steps of which comprise:
(a) providing a bundle of fibers;
(b) providing a heat curable composition comprising:
(i) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1), alkylene (when o is 2-4), carbonyl (when o is 2), thiol (when o is 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(ii) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups in liquid form;
(c) passing the bundle of fibers through the liquid heat curable composition to impregnate the bundle of fibers with the heat curable composition; and
(d) removing excess heat curable composition from the towpreg assembly, thereby forming a towpreg.
19. Cured reaction product of the towpreg of claim 17 .
20. Cured reaction product of the towpreg of claim 18 .
21. An adhesive film comprising a heat curable composition comprising:
(a) a benzoxazine component comprising
wherein o is 1-4, X is member selected from the group consisting of a direct bond (when o is 2), alkyl (when o is 1), alkylene (when o is 2-4) carbonyl (when o is 2) thiol (when o s 1), thioether (when o is 2), sulfoxide (when o is 2), and sulfone (when o is 2), and R 1 is alkyl; and
(b) about 5 weight percent or more of a toughener component comprising acrylonitrile-butadiene co-polymer having secondary amine terminal groups.
22. The adhesive film of claim 21 , further comprising a support selected from the group consisting of nylon, glass, carbon, polyester, polyalkylene, quartz, polybenzimidazole, polyetheretherketone, polyphenylene sulfide, poly p-phenylene benzobisoaxazole, silicon carbide, phenolformaldehyde, phthalate and napthenoate.
23. Cured reaction product of the adhesive film of claim 21 .