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AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsTerry L. St. Clair, Donald J. Progar
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The invention is a novel polyimide prepared from 3,4'-oxydianiline (3,4'-ODA) and 4,4'-oxydiphthalic anhydride (ODPA), in 2-methoxyethyl ether (diglyme). The polymer has been prepared in ultra high molecular weight and in a controlled molecular weight form which has a 2.5 percent offset is stoichiometry (excess diamine) with a 5.0 percent level of phthalic anhydride as an endcap. This controlled molecular weight form allows for greatly improved processing of the polymer for moldings, adhesive bonding, and composite fabrication. The higher molecular weight version affords tougher films and coatings. The overall polymer structure groups in the dianhydride, the diamine, and a metal linkage in the diamine affords adequate flow properties for making this polymer useful as a molding powder, adhesive, and matrix resin.
A high temperature polyimide composition prepared by reacting 4,4'-oxydiphthalic anhydride and 3,4'-oxydianiline.
A high temperature polyimide composition prepared by reacting 4,4'-oxydiphthalic anhydride and 3,4'-oxydianiline, at a concentration of approximately 30 weight percent or below, in 2-methoxyethyl ether.
A high temperature polyimide composition prepared by reacting 4,4'-oxydiphthalic anhydride and 3,4'-oxydianiline, at a concentration of approximately 30 weight percent or below, in 2-methoxyethyl ether, wherein the polyimide has been endcapped with about 5-10 mole percent of a monofunctional aromatic amine or a monofunctional aromatic anhydride and having unbalanced stoichiometry such that a molar deficit in the dianhydride is compensated with twice the molar amount of monofunctional aromatic amine, and the unbalanced stoichiometry is such that a 2.5-5.0 percent molar deficit exists for the 4,4'-oxydiphthalic anhydride and 5.0-10.0 mole percent of phthalic anhydride is used as the endcapper.
Dependencies are inferred from the claim text.