A curable composition containing more than 80% by weight of a blend of benzoxazines, wherein the blend includes (A) one or more multifunctional benzoxazines and (B) a liquid, non-halogenated monofunctional benzoxazine. This composition has been found to be stable at high temperatures, e.g. 180° C.-250° C., and suitable for making composite materials using conventional techniques such as prepregging and liquid resin infusion.

An apparatus for impregnating fiber structures with a matrix material includes a lower part having a bath for receiving the matrix material and a draining unit. The draining unit includes a wiper having a wiping edge, over which the impregnated fiber structure is guided during operation, and a surface inclined in the direction of the bath, by which matrix material draining from the fiber structure can return into the bath. The draining unit includes a cover on which a deflection unit, by which the fiber structure is pressed into the bath when the cover is mounted, is mounted. When the cover is mounted, a gap is formed between the cover and the lower part on the sides by which the fiber structure is guided into the apparatus and emerges from the apparatus. A method for impregnating fiber structures with a matrix material is also disclosed.

A composite material having at least two layers of reinforcing fibers impregnated with a curable resin; an interlaminar region formed between adjacent layers of reinforcing fibers; and a combination of polymeric toughening particles and fire-retardant particles in the interlaminar region.

Disclosed herein is an electrically conductive sized fiber including a fiber and a sizing composition adhered to a surface of the fiber, wherein the sizing composition includes at least one sizing compound and a plurality of graphene oxide nanoparticles, The present disclosure also discloses fiber-reinforced resin composites, articles including fiber-reinforced resin composites and methods of making such electrically conductive sized fiber and articles therefrom.

A laminate body is provided which contains a thin prepreg having a component (A) containing a matrix of reinforcing fiber, a component (B) containing a thermosetting resin, and a component (C) containing particles of a thermoplastic resin. When molded and cured out of autoclave, the laminate body achieves a fiber-reinforced composite having a low void ratio and providing excellent mechanical performance.

A method of producing a prepreg is described, in which a matrix resin is applied to a reinforcing fiber sheet in which the sheet can continuously run without clogging due to generated fuzz even at a high running speed and where the reinforcing fiber sheet can be efficiently impregnated with the matrix resin. A method of producing a prepreg includes allowing a reinforcing fiber sheet to pass substantially vertically downward through the inside of a coating section storing a matrix resin to apply the matrix resin to the reinforcing fiber sheet; and then applying a resin film to a primary impregnate prepreg withdrawn from the coating section.

A method of producing a prepreg is described, in which a matrix resin is applied to a reinforcing fiber sheet in which the sheet can continuously run without clogging due to generated fuzz even at a high running speed and where the reinforcing fiber sheet can be efficiently impregnated with the matrix resin. A method of producing a prepreg includes allowing a reinforcing fiber sheet to pass substantially vertically downward through the inside of a coating section storing a matrix resin to apply the matrix resin to the reinforcing fiber sheet; and then applying a resin film to a primary impregnate prepreg withdrawn from the coating section.

A resin composition includes: a vinyl-containing polyphenylene ether resin; a compound of Formula (1); and a compound of Formula (2), a compound of Formula (3), a compound of Formula (4) or a combination thereof. The resin composition may be used to make various articles, such as a prepreg, a resin film, a laminate or a printed circuit board, and at least one of the following improvements can be achieved, including prepreg viscosity variation ratio, prepreg stickiness resistance, amount of void after lamination, multi-layer board thermal resistance, glass transition temperature, ratio of thermal expansion, copper foil peeling strength, dissipation factor and laminate appearance.

A resin composition includes 100 parts by weight of a maleimide resin; 20 parts by weight to 60 parts by weight of a benzoxazine resin; 5 parts by weight to 40 parts by weight of an epoxy resin; 120 parts by weight to 240 parts by weight of silica including spherical silica having a sediment volume of less than or equal to 0.4 mL/g and a particle size distribution D50 of less than or equal to 1.0 μm; and 0.5 part by weight to 1.6 parts by weight of an imidazole compound having a long-chain alkyl group, wherein the imidazole compound having a long-chain alkyl group includes octylimidazole, undecylimidazole, heptadecylimidazole or a combination thereof. The resin composition may be used to make a prepreg, a resin film, a laminate or a printed circuit board, and at least one of the following improvements can be achieved, including glass transition temperature, ratio of thermal expansion, copper foil peeling strength, thermal resistance after moisture absorption, dissipation factor, amount of resin cluster and appearance of cooper-free circuit board.

The purpose of the present invention is to provide: a molding material from which a carbon fiber reinforced composite material having excellent impact resistance and tensile strength is obtained; and a molding material from which a glass fiber reinforced composite material, that has high bending strength and impact resistance, has excellent weather resistance, and can suppress a decrease in bending strength after water absorption, is obtained. In order to achieve the purpose, the molding material according to the present invention is a molding material formed of an epoxy resin composition and a carbon fiber and/or a glass fiber, wherein the epoxy resin composition includes all of [A] to [C], the carbon fiber satisfies conditions [a] and [b], and the glass fiber has a surface functional group capable of forming a covalent bond with an isocyanate group. [A] Epoxy resin having at least two oxylan groups in molecule [B] Epoxy resin curing agent having at least two isocyanate groups in molecule [C] Catalyst [a] Having substantially perfect circular cross section [b] Average fiber diameter of 4.0-8.0 μm