Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts. The prepreg includes carbon reinforcing fibers and an uncured resin matrix. The resin matrix includes an epoxy component that is a combination of a hydrocarbon epoxy novolac resin and a trifunctional epoxy resin and a tetrafunctional epoxy resin. The resin matrix includes polyethersulfone as a toughening agent and a thermoplastic particle component that includes a mixture of polyamide particles and polyimide particles.

Provided is a liquid crosslinking agent in which liquid life (pot life) as an undiluted solution is sufficiently long and excellent coating properties are exhibited when used. A liquid crosslinking agent containing an epoxy compound and an emulsifier, in which a content of water is 39% by mass or less with respect to a total amount of a liquid, and a contact angle with respect to a poly(ethylene-methacrylic acid) film when preparing an aqueous dispersion in which a concentration of a non-volatile component is 15% by mass is 42.0° or less. It is preferable that the epoxy compound has two or more epoxy groups in molecules, and it is preferable that the emulsifier is a nonionic surfactant. Provided is a coating method of a liquid crosslinking agent including diluting the liquid crosslinking agent with water to be used for coating.

An object of the present invention is to provide a novel fiber-reinforced epoxy resin material having improved strength. The fiber-reinforced epoxy resin material of the present invention comprises a cured product of an epoxy resin composition and a reinforcing fiber, wherein the epoxy resin composition comprises a novolac type epoxy resin as an epoxy resin component, and the cured product of the epoxy resin composition has a swelling ratio in a range from 20 mass % to 44 mass % in methyl ethyl ketone.

A self-adhesive prepreg comprising a fibre reinforcement layer having a first side and a second side, wherein the first side of the fibre reinforcement layer has been pre-impregnated with a self-adhesive resin composition. The self-adhesive may be used as a structural reinforcement and is especially adapted for direct bonding to oily steel or galvanized steel in the automotive, aerospace and other sheet metal fabrication industries.

The invention provides a method for preparing a fiber-reinforced part based on cyanate ester or a cyanate ester/epoxy blend, comprising the steps of (i) providing a liquid mixture comprising (a) from 15 to 99.9 wt. % of at least one di- or polyfunctional cyanate ester, (b) from 0 to 84.9 wt. % of at least one di- or polyfunctional epoxy resin, and (c) from 0.1 to 25 wt. % of a metal-free catalyst; (ii) providing a fiber structure (iii) placing said fiber structure in a mold or in a substrate, (iv) impregnating said fiber structure with said liquid mixture, (v) curing said liquid mixture by applying a temperature of 30 to 300° C. Using the method of the invention it is possible to produce in a short cycle time, using composite manufacturing processes such as resin transfer molding and infusing technology, fiber reinforced composite parts based on a cyanate ester or cyanate ester/epoxy resin formulation. The fiber-reinforced parts obtainable by the above method are also an object of the invention.

Methods and compositions are provided for the efficient and beneficial use of nanoparticulates, such as carbon nanotubes. In various embodiments, a nanoparticulate entrapped in a linear polymer, where the linear polymer is formed in the presence of the nanoparticulate, is provided. The entrapped nanoparticulate provides an efficient means to introduce nanoparticulates into compositions, such as resins and fiber-reinforced resins, allowing for increased dispersion and beneficial properties.

A curable epoxy composition comprising a polyvalent epoxy compound (A) having a biphenyl structure and/or condensed polycyclic structure, a trivalent or higher polyvalent phenol type epoxy compound (B), and a triazine structure-containing phenol resin (C) and a film, laminated film, prepreg, laminate, cured article, and composite article obtained using the same are provided.

The present invention provides thermosetting resin pre-impregnated or infused fiber materials or prepregs comprising a thermosetting resin mixture and a fiber material component of a heat resistant fiber, such as carbon fiber, having an areal weight of from 500 to 3,000 g/m2 having a coating of from 0.5 to 4 phr of a latent, particulate curative or solid curative, preferably, dicyandiamide, wherein the prepregs are infused with a thermosetting resin mixture comprising (a) at least one liquid epoxy resin, and (b) a hardener and/or a catalyst, as well as methods of making the same. The prepregs of present invention enables the simple provision of lightweight composites having consistent resin cure throughout.

The present technology provides an epoxy resin composition for a fiber-reinforced composite material, a method for producing an epoxy resin composition for a fiber-reinforced composite material, a prepreg, and a honeycomb panel. The epoxy resin composition for a fiber-reinforced composite material of the present technology contains: a reaction product obtained by reacting 100 parts by mass of a phosphorus-containing epoxy resin containing a phosphorus atom in the backbone thereof, and not less than 5 parts by mass and not greater than 20 parts by mass of an amino-terminated butadiene-acrylonitrile rubber; an epoxy resin other than the phosphorus-containing epoxy resin; a curing agent; and a curing accelerator.

The present invention relates to a prepreg which is manufactured by impregnating thermosetting resin composition and at least one thermoplastic additive into unidirectional carbon fiber, and to a resin composition for high speed curing prepreg for car body parts through press method and a prepreg product containing the same by differentiating a resin constituent, a resin equivalent weight, viscosity, gel time and glass transition temperature differing from those described in the prior art.