The present application provides a rapid curing epoxy resin composition for fiber-reinforced plastic materials that can be used with modern fast-cure heating systems without loss of heat resistance, surface quality, or mechanical properties of the cured epoxy matrix composite as well as prepregs and fiber-reinforced plastic materials based thereon as their matrix resins. The epoxy resin composition includes an epoxy resin, a dicyandiamide, an aromatic urea, and a clathrate complex comprising at least one compound selected from the group consisting of carboxylic acid compounds and tetrakisphenol compounds and at least one epoxy accelerator which is an imidazole and/or imidazoline.

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.

This invention relates to a composition comprising a semisolid epoxy resin containing a curative dispersed therein. The curative has a particle size such that at least 90% of the particles have a size below 25 pm at ambient temperature of 21° C., wherein the composition further comprises a diluent containing a particulate filler. The composition is used as matrix in prepregs. The use of the diluent increases peel strength of the composition when brought into contact with metal or wood substrate.

A resin composition capable of achieving a printed wiring board or the like excellent in heat dissipation properties, water absorption properties, copper foil peel strength, and heat resistance after moisture absorption is provided. A prepreg, a laminate, a metal foil clad laminate, a printed wiring board and the like, which use the resin composition are also provided. The resin composition of the present invention having at least an epoxy resin, a cyanate ester compound, and an inorganic filler, wherein the inorganic filler includes at least a surface-treated silicon carbide of a silicon carbide powder having at least a part of the surface treated with an inorganic oxide.

The invention discloses a carbon nanotube/polyetherimide/thermosetting resin dielectric composite and a preparation method therefor. 100 parts by weight of polyetherimide and 1-7 parts by weight of carbon nanotube are mixed uniformly in an Haake torque melt cavity to obtain a carbon nanotubes/polyetherimide composite; 20 parts of the carbon nanotube/polyetherimide composite are dissolved in 100-150 parts of dichloromethane, then the mixed solution is added in 100 parts of molten thermocurable thermosetting resin, mixing, and heat preserving, stirring are performed until a mixture is formed in a uniform state, and curing and post-treating are performed to obtain a carbon nanotube/thermosetting resin dielectric composite, wherein the substrate thereof has a typical reverse phase structure, while the carbon nanotubes are dispersed in a polyetherimide phase. The composite has a relatively low percolation threshold, a high dielectric constant and a low dielectric loss. The preparation method of the present invention has a simple process and is suitable for large-scale production.

The present invention provides a curable composition comprising a urethane-modified epoxy resin (A) as an essential component of a main material, and an acid anhydride (B) as an essential component of a curing agent, wherein the urethane-modified epoxy resin (A) is a reaction product of a polyisocyanate compound (a1), a polyester polyol (a2), and a hydroxyl group-containing epoxy resin (a3) as essential reaction raw materials. The curable composition of the invention is advantageous in that a cured product having excellent fracture toughness and excellent tensile strength can be formed from the composition.

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.