A fiber-modified interlayer includes a nonwoven fabric layer formed of continuous fibers, and discontinuous fibers attached to the nonwoven fabric, the fiber-modified interlayer is attached to at least one reinforcing layer of structural tows to form an interlayer-toughened reinforcing fabric, at least one layer of the interlayer-toughened reinforcing fabric is infused with a matrix material and cured to form a composite structure.

A method for reducing the resistivity of a carbon nanotube nonwoven sheet includes providing a carbon nanotube nonwoven sheet comprising a plurality of carbon nanotubes and applying pressure to the carbon nanotube nonwoven sheet to reduce air voids between carbon nanotubes within the carbon nanotube nonwoven sheet.

A method of producing carbon fiber, yarns, and nonwoven carbon fiber cloths, includes forming suitable polymeric precursor microfibers and/or nanofibers using a centrifugal spinning process and decomposing at least a portion of the polymeric precursor fibers to form carbon fibers. The decomposition may be accomplished by treating the polymeric precursor fibers with acid vapor from an aqueous acid solution at a temperature of less than 250 C.

A method of producing carbon fiber, yarns, and nonwoven carbon fiber cloths, includes forming suitable polymeric precursor microfibers and/or nanofibers using a centrifugal spinning process and decomposing at least a portion of the polymeric precursor fibers to form carbon fibers. The decomposition may be accomplished by treating the polymeric precursor fibers with acid vapor from an aqueous acid solution at a temperature of less than 250 C.

An object of the present invention is to provide a gas diffusion electrode substrate that can facilitate both the supply of a reaction gas to a gas diffusion electrode and discharge of water as a reaction product. The present invention provides a gas diffusion electrode substrate including a carbon fiber nonwoven fabric having 30/cm.sup.2 to 5000/cm.sup.2 discontinuous protrusions dispersedly formed on at least one surface thereof, and a water repellent imparted to the carbon fiber nonwoven fabric.

An object of the present invention is to provide a gas diffusion electrode substrate that can facilitate both the supply of a reaction gas to a gas diffusion electrode and discharge of water as a reaction product. The present invention provides a gas diffusion electrode substrate including a carbon fiber nonwoven fabric having 30/cm.sup.2 to 5000/cm.sup.2 discontinuous protrusions dispersedly formed on at least one surface thereof, and a water repellent imparted to the carbon fiber nonwoven fabric.

A method of manufacturing a composite product includes recovering a wet composite waste from at least one of the manufacturing process or an end-of-life product. The wet composite waste includes a first resin and a plurality of first fibers that are bound together with the first resin. The method also includes grinding the wet composite waste after recovering the wet composite waste. The method also includes mixing the wet composite waste with the second resin into a homogeneous mixture and placing the homogeneous mixture into a cavity. The method includes curing the second resin of the homogeneous mixture such that the homogenous mixture hardens to form a composite product that includes the first resin, the second resin, and the plurality of first fibers.

A method of manufacturing a composite product includes recovering a wet composite waste from at least one of the manufacturing process or an end-of-life product. The wet composite waste includes a first resin and a plurality of first fibers that are bound together with the first resin. The method also includes grinding the wet composite waste after recovering the wet composite waste. The method also includes mixing the wet composite waste with the second resin into a homogeneous mixture and placing the homogeneous mixture into a cavity. The method includes curing the second resin of the homogeneous mixture such that the homogenous mixture hardens to form a composite product that includes the first resin, the second resin, and the plurality of first fibers.

There is provided a random mat including reinforcing fibers having an average fiber length of 3 to 100 mm and a thermoplastic resin, wherein the reinforcing fibers satisfy the following i) to iii). i) The reinforcing fibers have a weight-average fiber width (Ww) which satisfies the following equation (1).

0 mm<Ww<2.8 mm (1) ii) The reinforcing fibers have an average-fiber-width dispersion ratio (Ww/Wn), which is defined as a ratio of the weight-average fiber width (Ww) to a number-average fiber width (Wn), of 1.00 or more and 2.00 or less. iii) The reinforcing fibers have a weight-average fiber thickness which is smaller than the weight-average fiber width (Ww) thereof.

There is provided a random mat including reinforcing fibers having an average fiber length of 3 to 100 mm and a thermoplastic resin, wherein the reinforcing fibers satisfy the following i) to iii). i) The reinforcing fibers have a weight-average fiber width (Ww) which satisfies the following equation (1).

0 mm<Ww<2.8 mm (1) ii) The reinforcing fibers have an average-fiber-width dispersion ratio (Ww/Wn), which is defined as a ratio of the weight-average fiber width (Ww) to a number-average fiber width (Wn), of 1.00 or more and 2.00 or less. iii) The reinforcing fibers have a weight-average fiber thickness which is smaller than the weight-average fiber width (Ww) thereof.