Sized carbon fibers, and thermoplastic polyester based composite structures employing the same
AssigneeCelanese Corporation
InventorsRobert Edelman, Paul E. McMahon, Gene P. Daumit
Life of this patent
Estimating the term…
Abstract
The present invention is directed to carbon fibers which are coated on the surface with a sizing agent of either a polyisocyanate, such as polymethylene polyphenyl polyisocyanate, or a sorbitol polyglycidyl ether having a specifically defined total chlorine content and epoxide equivalent weight. The coated carbon fibers are employed to prepare carbon fiber composites wherein the matrix resin is a thermoplastic polyester such as poly(1,4-butylene terephthalate). The matrix resin of the composite exhibits improved bonding with the coated carbon fibers thereby imparting improved interlaminar shear strength to the composite.
Claims7
At least one carbon fiber having coated on the surface thereof a sizing composition of sorbitol polyglycidyl ether having a total chlorine content of at least 10%, by weight, based on the weight of the sorbitol polyglycidyl ether, and an epoxide equivalent weight of from about 160 to about 230.
A composite structure comprising a continuous matrix of a thermoplastic polyester comprising a poly (alkylene terephthalate, isophthalate, or mixed terephthalate, isophthalate), said alkylene groups containing from about 2 to about 4 carbon atoms, and a reinforcing agent contiguous and firmly bonded thereto, said reinforcing agent comprising carbon fibers sized with a sizing composition of sorbitol polyglycidyl ether having a total chlorine content of at least 10%, by weight, based on the weight of the sorbitol polyglycidyl ether and an epoxide equivalent weight of from about 160 to about 230.
Dependencies are inferred from the claim text.