The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 23, 1986
Filed:
Dec. 24, 1984
Daniel A Scola, Glastonbury, CT (US);
Ruth H Pater, Rocky River, OH (US);
United Technologies Corporation, Hartford, CT (US);
Abstract
A low temperature processable moisture resistant polyimide and fiber reinforced composite of such a polymer and methods for making the same. The polyimide resin has repeating polymer units of the formula ##STR1## wherein n is 2 to about 20 and the molecular weight of the polymer chain is such that the polymer absorbs below about 0.2% by weight moisture at room temperature. The polyimide is made by reacting 4,4'(hexafluoroisopropylidene)bis(o-phthalic anhydride) with a diamine having the formula H.sub.2 N(CH.sub.2).sub.n NH.sub.2 wherein n is 2 to about 20 to form a polyamic acid. The polyamic acid is imidized to form the polyimide prepolymer and then further polymerized by exposing the polyimide prepolymer to heat to form the polymer described above. The composite can be made using the above process by coating fibers with the polyimide prepolymer, stacking layers of the coated fibers in a mold, and hot pressing the stacked impregnated fibers. The composite can also be made by coating fibers with 4,4'(hexafluoroisopropylidene)bis(o-phthalic anhydride) and a diamine as described above stacking layers of the coated fibers in a mold and hot pressing the stacked impregnated fibers.