A semipreg that can be cured/molded to form aerospace composite parts including rocket booster casings. The semipreg includes a fibrous layer and a resin layer located on one side of the fibrous layer. The resin layer includes an epoxy component that is a combination of a hydrocarbon epoxy novolac resin and a trifunctional epoxy resin and optionally a tetrafunctional epoxy resin. The resin matrix includes polyethersulfone as a toughening agent and a thermoplastic particle component.

Described herein are nanocomposites, methods of making nanocomposites, and methods of using nanocomposites. The nanocomposites include magnetite nanoparticles. The nanocomposites are useful in a variety of industrial applications.

Provided is a thermally-conductive resin composition containing a thermosetting resin and boron nitride particles, in which, in a case where a void fraction of the boron nitride particles relative to a compression pressure is measured, a void fraction at a compression pressure of 4 MPa is 30% or more and 60% or less, and a void fraction at a pressure of 8 MPa is 20% or more and 50% or less.

A fiber reinforced plastic material is provided. The fiber reinforced plastic material includes a plurality of carbon fibers, and a vinyl ester resin or unsaturated polyester resin containing at least one low coefficient of linear thermal expansion (CLTE) filler.

In the case of producing a fiber-reinforced composite material having excellent impact resistance by using an automatic lay up device, to provide a prepreg that can be layed up without adhesion and deposition of a part of the reinforced fibers or matrix resin in the device.

A prepreg containing the following components [A] to [E], wherein 85% by mass or more of the component [E] is present in a range within 9% of the average thickness of the prepreg from each surface of the prepreg, a range within 7% of the average thickness of the prepreg from each surface of the prepreg is composed of a first resin composition containing the components [B] to [E], and the prepreg satisfies the following conditions (I) to (V): [A] a carbon fiber, [B] an epoxy resin having two or more glycidyl groups in one molecule, [C] an aromatic amine compound, [D] a thermoplastic resin having a polyarylether skeleton, [E] a particle wherein primary particles have a number average particle size of 5 to 50 m, the content ratio (% by mass) of a thermoplastic resin and a thermosetting resin of 95:5 to 70:30, and a size of a crack generated when the particle is immersed in methyl ethyl ketone and boiled and refluxed for 24 hours is 20 m or less and the number of the crack is 5 or less; Condition (I): the component [B] contains 80% by mass or more of an epoxy resin having a viscosity at 25 C. of 2.010.sup.4 mPa.Math.s or more, Condition (II): a molar ratio of the number of active hydrogens in the component [C] to the number of epoxy groups in the component [B] is 0.7 to 1.3, Condition (III): the prepreg contains 15 to 25% by mass of the component [D] with respect to 100% by mass of the component [B], Condition (IV): the prepreg contains 50 to 80% by mass of the component [E] with respect to 100% by mass of the component [B], Condition (V): a minimum value of loss tangent tan of the first resin composition in the temperature range of 12 to 25 C. is 1.0 or less.

Thermosetting epoxy resin compositions on the one hand at room temperature in the incompletely cured state exhibit extremely slight alteration in shape and on the other hand develop a high surface tack, and, moreover, in the fully cured state are of high impact strength and at the same time exhibits high adhesion, particularly to metallic substrates. These compositions are ideally suited to the production of self-adhesive reinforcing elements.

The invention enhances the production efficiency in the production of prepreg by allowing the arrangement property and rectilinearity of reinforcing fibers to be well maintained, allowing the basis weight uniformity of an applied resin to be good, and further allowing a high line speed and suppression of contamination in the process to be achieved. The invention provides a method of producing a prepreg, which includes: discharging a molten resin from a discharge portion; introducing the discharged resin by an air flow; and capturing the discharged resin on a reinforcing fiber sheet conveyed continuously, wherein a key point is that the discharged resin is captured in a region in which the reinforcing fiber sheet is conveyed substantially in planar form.

The invention relates to a particulate curing component for a thermosetting resin, the particulate curing component comprising particles of a solid resin, wherein a curative for the thermosetting resin is dispersed within the particles of solid resin. The invention also relates to methods of forming particulate curing components and compositions comprising particulate curing components.

A sizing composition for reinforcing fibres is provided which makes it possible to improve the adhesion of these fibres with respect to an organic matrix that forms, with them, a part made of a composite material and that results from the chain transfer polymerization of a curable resin. The sizing composition includes a polybutadiene prepolymer comprising at least two epoxide functions, a cross-linking agent comprising at least two reactive functions, at least one of which is a thiol function; and a catalyst comprising at least one tertiary amine function. The sizing composition may be used in the following fields of use: aeronautical, aerospace, railway, naval and motor vehicle industries, for example, for the production of structural, engine, passenger compartment or body work parts; arms industry, for example, for the production of parts incorporated into the composition of missiles or missile launch tubes; sports and leisure goods industry, for example, for the production of goods intended for water sports and board sports.

A polymeric film or laminate comprising the same is applied to at least a portion of a surface of an underlying article to provide, for example, desired surface characteristics. To assist in such application, a polymerizable composition is coated onto at least one of the surface of the polymeric film or the laminate and the surface of the article. The polymerizable composition is then polymerized with the polymeric film or laminate positioned thereover to form a sufficiently polymerized interlayer between the polymeric film or laminate and the underlying surface in resulting articles. Ease of removal and/or repair of polymeric film and laminates comprising the polymeric film that are so applied is facilitated.