Structural panels and methods of making composite material for such structural panels may include applying a resin to a nonwoven fibrous web, where the nonwoven fibrous web includes a combination of glass fibers and polymer fibers. The web may be dried at a first stage temperature at or below a curing temperature of the resin for a time sufficient to substantially dry but not substantially cure the resin. The web may be laminated at a second stage temperature sufficient to fully cure the resin to produce a composite material. The second stage temperature may be above the melting point of the polymer fibers, and the resin may cause the composite material to retain a substantially rigid shape upon completion of the laminating operation.

A 3D object according to the invention involves substrate layers infiltrated by a hardened material. The 3D object may be fabricated by a method comprising the following steps: Flatten a substrate layer. Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Stack the substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers. In a preferred embodiment, the substrate is carbon fiber and excess substrate is removed by abrasion.

Fibrous material webs and methods of making the fibrous material webs. Binderless webs can be formed in a continuous process where fiber material, such as glass is melted and formed into fibers. The fibers are formed into a web of binderless glass fibers or a web with a dry binder. The binderless web or the web with dry binder can be layered and/or the fibers that make up the web can be mechanically entangled, for example, by needling.

Fibrous material webs and methods of making the fibrous material webs. Binderless webs can be formed in a continuous process where fiber material, such as glass is melted and formed into fibers. The fibers are formed into a web of binderless glass fibers or a web with a dry binder. The binderless web or the web with dry binder can be layered and/or the fibers that make up the web can be mechanically entangled, for example, by needling.

A 3D object according to the invention involves substrate layers infiltrated by a hardened material. The 3D object may be fabricated by a method comprising the following steps: Flatten a substrate layer. Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Stack the substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers. In a preferred embodiment, the substrate is carbon fiber and excess substrate is removed by abrasion. Flattening a substrate layer involves reducing planar inconsistencies or imperfections, and comprises applying heat to each substrate layer, cooling the substrate layers, and optionally applying tension and/or pressure to the heated and cooled substrate layers.

A nanotube-based insulator is provided having thermal insulating properties. The insulator can include a plurality of nanotube sheets stacked on top of one another. Each nanotube sheet can be defined by a plurality of carbon nanotubes. The plurality of carbon nanotubes can be configured so as to decrease normal-to-plane thermal conductivity while permitting in-plane thermal conductivity. A plurality of spacers can be situated between adjacent nanotube sheets so as to reduce interlayer contact between the nanotubes in each sheet. The plurality of spacers can be ceramic or alumina dots or provided by texturing the nanotube sheets.

A 3D object according to the invention involves substrate layers infiltrated by a hardened material. The 3D object may be fabricated by a method comprising the following steps: Flatten a substrate layer. Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Stack the substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers. In a preferred embodiment, the substrate is carbon fiber and excess substrate is removed by abrasion. Flattening a substrate layer involves reducing planar inconsistencies or imperfections, and comprises applying heat to each substrate layer, cooling the substrate layers, and optionally applying tension and/or pressure to the heated and cooled substrate layers.

A composite material, the composite material comprising at least one prepreg, said prepreg comprising at least one polymeric resin and at least one fibrous reinforcement; and conducting particles dispersed in the polymeric resin.