Abstract: Systems and methods for the reduction of volatile component content from shaped prepregs and prepreg layups and the layups and composites formed therefrom are disclosed. One or more shaped prepregs or prepreg layups are placed within an enclosure and a flow of a non-condensing gas is introduced adjacent at least one surface of the shaped prepregs or prepreg layups, accelerating the rate and/or the completeness of removal of volatile components from the shaped prepregs or prepreg layups. The shaped prepregs or prepreg layups may be further subjected to heat, vacuum, and external pressure to facilitate removal of the volatile components. Shaped prepregs and prepreg layups with volatiles reduced in this manner may be further consolidated with heat, external pressure and/or vacuum. Beneficially, reduced matrix bleed and reduced fiber movement may be achieved during processing, reducing manufacturing time and improving part quality.

Abstract: Systems and methods for the fabrication of prepregs possessing enhanced ability for the removal of gases from within prepregs and prepreg layups prior to and/or during at least a portion of consolidation and cure process to form composite structures are disclosed. In certain embodiments, perforations of selected configurations may be introduced into the prepregs prior to, during, and after layup. The perforations provide routes for gases trapped within and between the perforated prepregs and prepreg lay-ups to escape during consolidation and cure process, reducing the residual porosity within the resulting composite. For example, composites having residual porosities less than 10 vol. %, on the basis of the volume of the composite, may be achieved in this manner.

Abstract: Particle toughened, fiber-reinforced composites include a fiber region and an interlayer region between the fibers. The fiber region includes a plurality of fibers at least partially within a first polymer composition including a first base polymer formulation and a first plurality of toughening particles. The interlayer region includes a second polymer composition including a second base polymer formulation and at least one of the first plurality of toughening particles and a second plurality of toughening particles. Examples of first and second pluralities of toughening particles, respectively, may include core shell rubbers and polyimides. Increasing concentration of the first plurality of toughening particles may improve the composite toughness while preserving thermal properties of the composite, such as weight loss after extended duration exposure to elevated temperature.

Abstract: Particle-toughened polymer compositions include a base polymer formulation and a plurality of toughening particles. In certain embodiments, the base polymer formulation includes bismaleimides or other polymer resins capable of high temperature service. A first plurality of toughening particles may include core shell rubbers. A second plurality of toughening particles may be selected from a variety of polymer compositions, including polyimides, polyether ketone (PEK), polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polyether imide, polyether sulfones, and polyphenylene oxide. It is found that increasing concentration of the core shell rubbers may improve the toughness of the composition while preserving thermal properties of the composition, such as glass transition temperature.

Abstract: Particle toughened, fiber-reinforced composites include a fiber region and an interlayer region between the fibers. The fiber region includes a plurality of fibers at least partially within a first polymer composition including a first base polymer formulation and a first plurality of toughening particles. The interlayer region includes a second polymer composition including a second base polymer formulation and at least one of the first plurality of toughening particles and a second plurality of toughening particles. Examples of first and second pluralities of toughening particles, respectively, may include core shell rubbers and polyimides. Increasing concentration of the first plurality of toughening particles may improve the composite toughness while preserving thermal properties of the composite, such as weight loss after extended duration exposure to elevated temperature.

Abstract: Particle toughened, fiber-reinforced composites include a fiber region and an interlayer region between the fibers. The fiber region includes a plurality of fibers at least partially within a first polymer composition including a first base polymer formulation and a first plurality of toughening particles. The interlayer region includes a second polymer composition including a second base polymer formulation and at least one of the first plurality of toughening particles and a second plurality of toughening particles. Examples of first and second pluralities of toughening particles, respectively, may include core shell rubbers and polyimides. Increasing concentration of the first plurality of toughening particles may improve the composite toughness while preserving thermal properties of the composite, such as weight loss after extended duration exposure to elevated temperature.

Abstract: Particle toughened, fiber-reinforced composites include a fiber region and an interlayer region between the fibers. The fiber region includes a plurality of fibers at least partially within a first polymer composition including a first base polymer formulation and a first plurality of toughening particles. The interlayer region includes a second polymer composition including a second base polymer formulation and at least one of the first plurality of toughening particles and a second plurality of toughening particles. Examples of first and second pluralities of toughening particles, respectively, may include core shell rubbers and polyimides. Increasing concentration of the first plurality of toughening particles may improve the composite toughness while preserving thermal properties of the composite, such as weight loss after extended duration exposure to elevated temperature.

Abstract: Particle-toughened polymer compositions include a base polymer formulation and a plurality of toughening particles. In certain embodiments, the base polymer formulation includes bismaleimides or other polymer resins capable of high temperature service. A first plurality of toughening particles may include core shell rubbers. A second plurality of toughening particles may be selected from a variety of polymer compositions, including polyimides, polyether ketone (PEK), polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polyether imide, polyether sulfones, and polyphenylene oxide. It is found that increasing concentration of the core shell rubbers may improve the toughness of the composition while preserving thermal properties of the composition, such as glass transition temperature.

Abstract: Polymer compositions capable of a high degree of curing at relatively low temperatures, and prepregs, adhesives, films and composites formed therefrom are discussed. The polymer compositions include epoxy resin systems and a dual curing system including one or more curing agents containing one or more hydrazine-based curing agents having hydrazine functional groups and one or more amine-based curing agents containing one or more amine functional groups. The hydrazine-amine curing systems enable the polymer composition to achieve elevated levels of gelation or degree of cure at lower temperatures than are achievable with amine functional curing agents alone.

Abstract: Systems and methods for the fabrication of prepregs possessing enhanced ability for the removal of gases from within prepregs and prepreg layups prior to and/or during at least a portion of consolidation and cure process to form composite structures are disclosed. In certain embodiments, perforations of selected configurations may be introduced into the prepregs prior to, during, and after layup. The perforations provide routes for gases trapped within and between the perforated prepregs and prepreg lay-ups to escape during consolidation and cure process, reducing the residual porosity within the resulting composite. For example, composites having residual porosities less than 10 vol. %, on the basis of the volume of the composite, may be achieved in this manner.

Abstract: Systems and methods for the reduction of volatile component content from shaped prepregs and prepreg layups and the layups and composites formed therefrom are disclosed. One or more shaped prepregs or prepreg layups are placed within an enclosure and a flow of a non-condensing gas is introduced adjacent at least one surface of the shaped prepregs or prepreg layups, accelerating the rate and/or the completeness of removal of volatile components from the shaped prepregs or prepreg layups. The shaped prepregs or prepreg layups may be further subjected to heat, vacuum, and external pressure to facilitate removal of the volatile components. Shaped prepregs and prepreg layups with volatiles reduced in this manner may be further consolidated with heat, external pressure and/or vacuum. Beneficially, reduced matrix bleed and reduced fiber movement may be achieved during processing, reducing manufacturing time and improving part quality.

Abstract: Thermosetting polymers with high temperature capability and superior oxidative stability for composite and adhesive applications are disclosed. These polymers are ideally suited for adhesives and RTM, resin film infusion, and prepreg methods to make polymer matrix, fiber reinforced composite parts.

Abstract: Thermosetting polymers with high temperature capability for composite and adhesive applications are disclosed. Inhibitors for improving pot life, gel time and storage stability are disclosed. These polymers are ideally suited for adhesives and RTM, resin film infusion, and prepreg methods to make polymer matrix, fiber reinforced composite parts.

Abstract: Fiber-reinforced prepregs with superior tack containing thermosetting resin systems containing particulate, elastomers having a Tg of 25.degree. C. and below, as well as the composites prepared therefrom are disclosed.