Bonding of composite materials
AssigneeCytec Industries Inc.
InventorsLeonard MacAdams, Dalip Kohli
Life of this patent
Estimating the term…
Abstract
Peel ply for surface preparation and a method of surface preparation prior to adhesive bonding. A resin-rich peel ply is applied onto a curable, resin-based composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the matrix resin in the peel ply remains partially cured. When the peel ply is removed, a roughened, bondable surface with chemically-active functional groups is revealed. The composite substrate with the chemically-active, bondable surface may be bonded to another composite substrate to form a covalently-bonded structure.
Claims13
A method for surface preparation prior to adhesive bonding comprising:
- (a) providing a composite substrate comprising reinforcing fibers impregnated with a curable, first matrix resin;
- (b) applying a removable, resin-rich peel ply onto a surface of the composite substrate, said peel ply comprising a woven fabric impregnated with a curable, second matrix resin different from the first matrix resin;
- (c) co-curing the composite substrate and the peel ply until the composite substrate is fully cured but the second matrix resin in the peel ply remains partially cured;
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- (d) removing the peel ply from the composite substrate's surface, leaving a thin film of partially cured second matrix resin on the composite substrate's surface, said thin film providing a roughened, bondable surface with chemically-active functional groups.
A bonding method comprising:
- (a) providing a first composite substrate comprising reinforcing fibers impregnated with a curable, first matrix resin;
- (b) applying a removable, resin-rich peel ply onto a surface of the first composite substrate, said peel ply comprising a woven fabric impregnated with a curable, second resin matrix different from the first matrix resin;
- (c) co-curing the first composite substrate and the peel ply until the first composite substrate is fully cured but the second matrix resin in the peel ply remains partially cured;
- (d) removing the peel ply from the first composite substrate's surface, leaving a thin film of partially cured second matrix resin on the first composite substrate's surface, said thin film providing a roughened, bondable surface with chemically-active functional groups;
- (e) joining the cured, first composite substrate to a second composite substrate with a curable adhesive film in between the composite substrates, said adhesive film being in contact with the bondable surface of the first composite substrate, wherein the curable adhesive film comprises chemically-active functional groups capable of reacting with the chemically-active functional groups on the bondable surface of the first composite substrate;
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- (f) curing the adhesive film to form a covalently bonded structure, whereby the functional groups on the adhesive film react with the functional groups on the bondable surface of the first composite substrate to form covalent bonds.
Dependencies are inferred from the claim text.