Apparatus and associated methods relate to an enhanced auxetic composite material (EACM) of a base thermoplastic elastomer (TPE) and/or a thermoset material combined with an auxetic material, the composite formed with a molding process, where the base material is injected or dripped into or injected, dripped or formed around the auxetic material, the composite material providing higher impact performance than the individual materials. In an illustrative example, combining various energy absorbing materials with auxetic materials may further enhance impact performance. In some examples, TPE material injected into auxetic structures may fill internal voids. In some examples, the auxetic material may be suspended within the TPE material and be encapsulated around the auxetic material form. Auxetic materials may take various forms, for example, sheets, 3-D structures, and particles, each providing unique benefits. Various embodiments included within various personal protection articles may advantageously provide long life and enhance impact resistance.

Methods and apparatus to increase strength and toughness of aircraft structural components are disclosed. An example apparatus includes a composite structure of an aircraft, a stringer coupled to the composite structure of the aircraft, where the stringer and the composite structure form a stringer radius gap. A gap filler is disposed in the stringer radius gap, which includes chopped fibers randomly distributed throughout an entire volume of the gap filler.

A composite material and method of producing a composite material for use in fabrication, building and construction is disclosed. A composition as disclosed herein comprises a high proportion of particulate waste material dispersed in a matrix of thermoplastic polymer and wax. A method of producing a composite material comprises melt mixing thermoplastic polymer and wax with a particulate material, thereby dispersing the particulate material in a melt mixture of the composite material.

Provided herein according to some embodiments is a dual cure stereolithography resin that includes thermoplastic particles, which thermoplastic particles are insoluble in the resin and insoluble during a first, light, cure in which an intermediate object is produced, but then dissolve or swell in the intermediate object during the second, heat, cure.

Provided herein according to some embodiments is a dual cure stereolithography resin that includes a Diels-Alder adduct, which adduct is light polymerizable in the first, light, cure to produce an intermediate object, and on heating the intermediate object yields a bis-maleimide that can further react and/or polymerize during the second, heat, cure.

The present invention relates to a method of forming a molded fibrous product, comprising the steps of foaming an aqueous suspension of natural fibers, optionally in combination with synthetic fibers, to provide a first fibrous foam, a surfactant may be added to aid the foaming, feeding the fibrous foam into a mold, mechanically withdrawing a part of the water contained in the foam to produce a solidified, moist fibrous composition, and evaporating water from the solidified, moist fibrous composition to produce a dry fibrous product.

Methods and apparatus to increase strength and toughness of aircraft structural components are disclosed. An example apparatus includes a composite structure of an aircraft, a stringer coupled to the composite structure of the aircraft, where the stringer and the composite structure form a stringer radius gap. A gap filler is disposed in the stringer radius gap, which includes chopped fibers randomly distributed throughout an entire volume of the gap filler.

Apparatus and associated methods relate to an enhanced auxetic composite material (EACM) of a base thermoplastic elastomer (TPE) and/or a thermoset material combined with an auxetic material, the composite formed with a molding process, where the base material is injected or dripped into or injected, dripped or formed around the auxetic material, the composite material providing higher impact performance than the individual materials. In an illustrative example, combining various energy absorbing materials with auxetic materials may further enhance impact performance. In some examples, TPE material injected into auxetic structures may fill internal voids. In some examples, the auxetic material may be suspended within the TPE material and be encapsulated around the auxetic material form. Auxetic materials may take various forms, for example, sheets, 3-D structures, and particles, each providing unique benefits. Various embodiments included within various personal protection articles may advantageously provide long life and enhance impact resistance.

A method for assembling a stiffened composite structure includes a step of co-bonding a cured infused composite stiffener to a pre-preg composite laminate skin element, wherein the pre-preg composite laminate skin element is dimensionally changeable. Another method for assembling a stiffened composite structure includes a step of coupling a cured infused composite stiffener which includes a preform of a plurality of braided fibers to a pre-preg composite laminate skin element, wherein the pre-preg composite laminate skin element is dimensionally changeable.

The invention relates to a method for impregnating at least one fibre bundle (11) with a high-viscosity plastics material (13), said method comprising the following steps: providing at least one fibre bundle (11) for impregnation, formed of a multiplicity of continuous fibres, and providing a plastics material (13), melted at a mandated operating temperature and of high viscosity, and impregnating the fibre bundle (11) with the plastics material (13), by guiding the fibre bundle for impregnation continuously through an impregnation cavity (12), filled with the melted plastics material (13), where during impregnation of the fibre bundle, the melted plastics material within the impregnation cavity is contacted with a surface (15) of at least one oscillation generator (14) in such a way that sonic energy is introduced by said oscillation generator into the melted high-viscosity plastics material in the impregnation cavity.