摘要:
Radomes having increased transparency and reduced reflectivity and refractivity to radar waves may be prepared or repaired utilizing heat-curable resin-containing structural materials in which the heat-curable resin contains greater than about 70 weight percent of cyanate functional monomers. The structural materials take the form of matrix resin impregnated prepegs and composites, film adhesives, paste adhesives, syntactic foams, and expandable foams, and may be used to prepare numerous useful structural features including honeycomb materials and leading edge radomes containing syntactic foams. The heat-curable resins further facilitate the preparation of low observable structures.
摘要:
Toughened bismaleimide resin systems capable of preparing carbon fiber reinforced composites having compression after impact strengths of greater than 40 Ksi are prepared from bismaleimide matrix resin systems containing a member of a limited set of soluble thermoplastic polyimides in particulate form.
摘要:
The incorporation of 2 to 25 .mu.m particles of a limited class of polyimides having appreciable nonaromatic character into heat curable epoxy resin systems significantly increases the toughness of such systems without loss of other desirable properties. These toughened epoxy resin systems are useful in preparing carbon fiber reinforced composites having compression strength after impact (CAI) of greater than 45 Ksi after a 1500 in-lb/in impact.
摘要:
Bismaleimide resin systems containing one or more bismaleimides and an alkenyl and/or alkynyl substituted phenylated dicyclopentadiene comonomer have high glass transition temperatures and impact resistance.
摘要:
The use of organophosphines, organophosphonium salts or organophosphine complexes as cure catalysts in the cure of maleimide resin systems produces products having excellent physical properties and improved gel times. These systems are especially useful in the production of advanced structural composites.
摘要:
Bismaleimide resin systems and fiber reinforced prepregs prepared therefrom having exceptional toughness are prepared by dispersing into a bismaleimide base resin system preformed functionalized elastomer particles having a T.sub.g of less than 10.degree. C.
摘要:
Heat-curable bismaleimide resins contain a bismaleimide, an aromatic dialkenyl compound as comonomer and also from 1 to 40% by weight of a monoalkenyl compound, preferably 2-hydroxy-3-allylbiphenyl, as reactive diluent.
摘要:
Chain extended tougheners derived from the reaction of a propenylphenol, a di- or polyphenol, and an epoxy resin may be used to increase the toughness of bismaleimide resin systems.
摘要:
The use of organophosphines, organophosphonium salts or organophosphine complexes as cure catalysts in the cure of maleimide resin systems produces products having excellent physical properties and improved gel times. These systems are especially useful in the production of advanced structural composites.
摘要:
Galvanic degradation under salt spray or salt water conditions in hybrid structures containing a corrosible metal and a conductive-fiber reinforced polymer matrix composite is reduced through the addition to the polymer matrix of the composite of an effective amount of an inorganic corrosion/degradation inhibitor.