Abstract: A tailorable polyimide prepolymer blend comprising an end group component, a dianhydride component, and a diamine component. The dianhydride component includes at least 3,4,3?,4?-benzophenonetetracarboxylic dianhydride (BTDA), derivatives thereof, or combinations thereof, and 3,4,3?,4?-biphenyltetracarboxylic dianhydride (BPDA), derivatives thereof, or combinations thereof. The diamine component includes at least 1,3-phenylenediamine (mPDA), derivatives thereof, or combinations thereof; 1,4-phenylenediamine (pPDA), derivatives thereof, or combinations thereof; bis amino phenoxy benzene (APB), derivatives thereof, and combinations thereof; and optionally, 4,4?-(1,3-phenylene-bis(1-methylethylidene)bisaniline (Bis-M), derivatives thereof, and combinations thereof. A cured polyimide matrix has a glass transition temperature of at least about 450° F. (232° C.).

Abstract: A method for fabricating a turbine engine composite containment casing is provided. The method comprising impregnating a plurality of fiber-reinforced layers with a resin to form a preform, heating the preform to a first temperature, applying a vacuum to the preform, varying an amount of pressure applied to the preform when the temperature reaches the first temperature, heating the preform from the first temperature to a second temperature at a first temperature rate, and heating the preform from the second temperature to a third temperature at a second temperature rate to facilitate curing of the preform.

Abstract: A tailorable polyimide prepolymer blend comprising an end group component, a dianhydride component, and a diamine component. The dianhydride component includes at least 3,4,3?,4?-benzophenonetetracarboxylic dianhydride (BTDA), derivatives thereof, or combinations thereof, and 3,4,3?,4?-biphenyltetracarboxylic dianhydride (BPDA), derivatives thereof, or combinations thereof. The diamine component includes at least 1,3-phenylenediamine (mPDA), derivatives thereof, or combinations thereof, 1,4-phenylenediamine (pPDA), derivatives thereof, or combinations thereof, bis amino phenoxy benzene (APB), derivatives thereof, and combinations thereof, and optionally, 4,4?-(1,3-phenylene-bis(1-methylethylidene) bisaniline (Bis-M), derivatives thereof, and combinations thereof. A cured polyimide matrix has a glass transition temperature of at least about 450° F. (232° C.).

Abstract: A tailorable polyimide prepolymer blend including a diamine component including 1,3-phenylenediamine (mPDA), Bisaniline M, and 1,4-phenylenediamine (pPDA), a dianhydride component including 3,4,3?,4?-benzophenonetetracarboxylic dianhydride (BTDA) and 3,4,3?,4?-biphenyltetracarboxylic dianhydride (BPDA), and an end group component. The components may be provided as a monomeric mixture. The prepolymer blend, prior to cure, may provide at least one predetermined prepolymer blend property; and the cured prepolymer blend may provide a crosslinked polyimide matrix having at least one predetermined crosslinked matrix property. Articles formed from the tailorable polyimide prepolymer blend may include powders, neat resins, coating materials, films, adhesives, fibers, composites, laminates, prepregs and parts.

Abstract: A crosslinked polyimide copolymer having a crosslinked matrix including an R1 group and a an R2 group, and/or an M group. The R1 group and R2 group independently comprise the formula: wherein V is a tetravalent substituted or unsubstited aromatic monocyclie or polycyclic linking structure; and R is a substituted or unsubstituted divalent organic radical. R2 structure is different than the structure for R1. The M group, when present, is selected from the group consisting of a diamine structure, a dianhydride structure and an end group structure, with the M group being in the reacted or unreacted form.

Abstract: A process for making a crosslinked polyimide copolymer. The process includes providing a prepolymer mixture, providing a fiber and contacting the prepolymer mixture with the fiber. The prepolymer mixture in contact with the fiber is the cured at a temperature and pressure sufficient to provide a crosslinked polyimide copolymer having a low void content and a glass transition temperature of greater than about 450° F.

Abstract: A polyimide prepolymer mixture for preparing polyimide resins having a blend of a first prepolymer component and a second prepolymer component. The first prepolymer component has the formula, E1-[R1]n-E1 and the second prepolymer component has the formula E2-[R2]n-E2, M1, or a combinations thereof. R1 and R2 have the formula: In the formulas, n is from about 1 to about 4; V is a tetravalent substituted or unsubstituted aromatic monocyclic or polycyclic linking structure; R is a substituted or unsubstituted divalent organic radical; E1 and E2 include functional groups that form oligomer compounds with the R1 and R2 formulas and E1 and E2 further include crosslinkable functional groups M1 includes a mixture of compounds selected from the group consisting of diamine compounds, dianhydride compounds, end group compounds, and combinations thereof.

Abstract: A method for making a copolymer polyimide resins. The method includes providing a first prepolymer component and a second prepolymer component. The first prepolymer component has the formula, E1-[R1]n-E1 and the second prepolymer component has the formula E2-[R2]n-E2, M1, or a combinations thereof. R1 and R2 have the formula: In the formulas, n is from about 1 to about 4; V is a tetravalent aromatic monocyclic or polycyclic linking structure; R is a divalent organic radical; E1 and E2 include crosslinkable functional groups. M1 includes a mixture of compounds selected from the group consisting of diamine compounds, dianhydride compounds, end group compounds, and combinations thereof. The process further includes blending the first and second prepolymer components to form a prepolymer mixture having a glass transition temperature of the mixture is greater than about 450° F. or the melt viscosity of the mixture is less than about 1000 centipoise.

Abstract: A gas turbine engine component comprising a fiber reinforced matrix. The matrix includes a crosslinked matrix including an R1 group and a an R2 group, and/or an M group. The R1 group and R2 group independently comprise the formula: wherein V is a tetravalent substituted or unsubstituted aromatic monocyclie or polycyclic linking structure; and R is a substituted or unsubstituted divalent organic radical. R2 structure is different than the structure for R1. The M group, when present, is selected from the group consisting of a diamine structure, a dianhydride structure and an end group structure, with the M group being in the reacted or unreacted form. The crosslinked matrix has a glass transition temperature and a thermal oxidative stability sufficient to provide component stability for operational temperature up to about 550° F.

Abstract: A method for fabricating a reinforced matrix composite comprising the step of providing a composite preform having a fibrous structure and applying matrix material onto the preform in locations along the preform. A barrier material is applied to at least a portion of the coated preform to direct the flow of matrix material into the preform. The composite preform is heated to a temperature sufficient to render the matrix material viscous and insufficient to cure the matrix material. The pressure to the interior of the composite preform is reduced, while the pressure to the barrier material is increased. The temperature is maintained to flow the matrix material into the composite preform and to force gases from the fibrous structure. The composite preform is then cured and cooled to form a reinforced matrix composite having a low void content and a substantially uniform matrix distribution.

Abstract: A reinforced matrix composite containment duct for gas turbine engines comprising a reinforced matrix composite containment duct having high strength integral flanges and pre-stressed reinforcing fibers, the reinforced matrix composite having uniform distribution of matrix material; and the reinforced matrix composite having less than or equal to 2.5% void space.