Abstract: One or more layers of structured thermoplastic polymer are located within the interleaf zones of a preform or prepreg. The structured thermoplastic polymer is a film or membrane formed by: a) dissolving polyethersulfone or polyetherimide in a solvent to form a polymer dope; b) dispersing a curing agent for an epoxy resin in the polymer dope to form a curative-enriched polymer dope; c) casting the curative-enriched polymer dope onto a surface to form a dope layer; and d) removing the solvent from the dope layer to form a layer of structured thermoplastic polymer.

Abstract: A structural panel comprising an internal core material having first and second opposing faces, first and second face sheets bonded to the first and second opposing faces respectively, wherein the panel comprises an open-structured sheet, interposed between a first face of the core material and its respective face sheet and the panel comprises less than 200 gsm adhesive.

Abstract: Thermosetting resins are provided that are toughened with an irradiated thermoplastic toughening agent and which have reduced levels of solvent-induced micro crack formation. The thermoplastic toughening agent is treated with a sufficient amount of high-energy radiation (e.g. electron beam or gamma rays) to cause a reduction in solvent-induced micro crack formation in the cured resin when compared to the same toughened thermosetting resin in which the non-irradiated version of the thermoplastic toughening agent is used.

Abstract: A curable prepreg or semipreg material comprising a layer of fibers and a substantially non-flowable curable resin having a layer of porous sheet material on an outer surface, the material allows automatic lay-up of high fiber content prepregs or semiprepregs typically used in industrial applications such as wind turbine blades.

Abstract: The processing window for thermosetting resins that contain particulate hardeners is prolonged using the combined steps of heat-treating the resin to form a low-viscosity resin mixture in which the particles are dissolved and then molding the low-viscosity resin mixture at temperatures below the dissolution temperature of the particles to infuse a fibrous preform. The infused resin preform is heated to the curing temperature of the resin to provide final curing of the resin.

Abstract: A resin composition that is storable at ambient temperatures. The resin composition forms a cured resin when exposed to a curing agent and heated to a curing temperature that is relatively close to ambient temperature. The resin composition includes a resin component that is composed of a liquid part that is made up of one or more liquid thermosetting resins and a solid part that includes particles of one or more solid thermosetting resins. The liquid part further includes a gelation agent that is present in a sufficient amount to maintain the particles in suspension within the liquid part at ambient temperatures. The viscosity of the resin component changes from a high viscosity state to a low viscosity state when the temperature is increased from ambient temperature to the curing temperature. The high viscosity state is substantially more viscous than the low viscosity state.

Abstract: A structural panel comprising an internal core material having first and second opposing faces, first and second face sheets bonded to the first and second opposing faces respectively, wherein the panel comprises an open-structured sheet, interposed between a first face of the core material and its respective face sheet and the panel comprises less than 200 gsm adhesive.

Abstract: Thermosetting resins are provided that are toughened with an irradiated thermoplastic toughening agent. The resins have reduced levels of solvent-induced micro crack formation and do not lose their adhesiveness when attacked by solvent. The thermoplastic toughening agent is treated with a sufficient amount of high-energy radiation (e.g. electron beam or gamma rays) to cause reductions in solvent-induced micro crack formation and solvent-induced loss of adhesiveness when compared to the same toughened thermosetting resin in which a non-irradiated version of the thermoplastic toughening agent is used.

Abstract: A resin composition that is storable at ambient temperatures. The resin composition forms a cured resin when exposed to a curing agent and heated to a curing temperature that is relatively close to ambient temperature. The resin composition includes a crystalline resin component that is sandwiched between two non-crystalline resin components to provide a zone that is rich in crystalline thermosetting resin. The crystalline thermosetting resin has a melting point that is above ambient temperature, but below the curing temperature. The viscosity of the resin component changes from a high viscosity state to a low viscosity state when the temperature is increased from ambient temperature to the curing temperature.

Abstract: A composite material, the composite material comprising at least one prepreg, said prepreg comprising at least one polymeric resin and at least one fibrous reinforcement; and conducting particles dispersed in the polymeric resin.

Abstract: An uncured fiber reinforced assembly that includes a reinforcement layer containing a fibrous material and at least one highly reactive curing agent. A matrix film layer is applied to the reinforcement layer so that it does not substantially impregnate the reinforcement layer. The matrix film layer includes at least one uncured epoxy resin and at least one latent epoxy curing agent. The assembly is designed for use in making snowboards and skis.

Abstract: The processing window for thermosetting resins that contain particulate hardeners is prolonged using the combined steps of heat-treating the resin to form a low-viscosity resin mixture in which the particles are dissolved and then moulding the low-viscosity resin mixture at temperatures below the dissolution temperature of the particles to infuse a fibrous preform. The infused resin preform is heated to the curing temperature of the resin to provide final curing of the resin.

Abstract: A curable prepreg comprising a structural layer of conductive fibres and a first outer layer of thermosetting resin, the resin layer comprising thermoplastic particles and glassy carbon particles provides improved electrical conductivity and excellent mechanical properties.

Abstract: A curable prepreg or semipreg material comprising a layer of fibres and a substantially non-flowable curable resin having a layer of porous sheet material on an outer surface, the material allows automatic lay-up of high fibre content prepregs or semiprepregs typically used in industrial applications such as wind turbine blades.

Abstract: A process for the manufacture of a prepreg comprising feeding a layer of unidirectional conductive fibres having a defined width, bringing into contact with a first face of the fibres a first layer of resin comprising thermosetting resin, and compressing the resin and fibres together by passing over one or more impregnation rollers, wherein the pressure exerted onto the conductive fibres and resin does not exceed 40 kg per centimetre of the width of the conductive fibres, and the resin being in sufficient amount for the resin to enter the interstices of the fibres and leave a first outer layer of resin essentially free of unidirectional conductive fibres.

Abstract: A resin composition that is storable at ambient temperatures. The resin composition forms a cured resin when exposed to a curing agent and heated to a curing temperature that is relatively close to ambient temperature. The resin composition includes a resin component that is composed of a liquid part that is made up of one or more liquid thermosetting resins and a solid part that includes particles of one or more solid thermosetting resins. The liquid part further includes a gelation agent that is present in a sufficient amount to maintain the particles in suspension within the liquid part at ambient temperatures. The viscosity of the resin component changes from a high viscosity state to a low viscosity state when the temperature is increased from ambient temperature to the curing temperature. The high viscosity state is substantially more viscous than the low viscosity state.

Abstract: A composite material, the composite material comprising at least one prepreg, said prepreg comprising at least one polymeric resin and at least one fibrous reinforcement; and conducting particles dispersed in the polymeric resin.

Abstract: Molding material that includes a layer of fibrous reinforcing material having one surface on which a first layer of a resin partially impregnates the fibrous material and a further resin layer located on the opposite surface which retains in position surface fibers of the fibrous material. The further resin layer is of lower weight than the first layer and is formed as an openwork structure with a solid part and spaces through which the fibrous material is exposed.

Abstract: Pre-impregnated composite material (prepreg) is provided that can be cured to form composite parts that have high levels of damage tolerance. The matrix resin includes a thermoplastic particle component that is a blend of particles that have a melting point above the curing temperature and particles that have a melting point at or below the curing temperature.

Abstract: One or more layers of structured thermoplastic polymer, such as a light weight veil of thermoplastic polymer fibers, are located within the interleaf zone of laminates that are composed of fibrous layers and thermosetting resin. The thermoplastic veils are used in the interleaf zones as a replacement for thermoplastic toughening particles. The structured thermoplastic polymer may be coated with a conductive material to improve electrical conductivity through the laminate.