Abstract: A resin composition comprising: (i) one or more polymerisable liquid thermoset resin components; (ii) optionally one or more curing agents for said one or more polymerisable liquid resin components; and (iii) at least one gelator, wherein said gelator interacts within said composition to form a gel at ambient temperatures, said gel being thermally reversible such that the gelled composition can undergo a transition from the gelled state to a state of lower viscosity when the composition is treated to facilitate the cure of said polymerisable resin component.

Abstract: Composite materials composed of a structural fibrous reinforcement and a matrix resin composition. The matrix resin composition includes at least one thermoset resin component, at least one curative component and at least one inorganic nano-scale particulate. The cured composite material exhibits a fatigue performance such that it achieves greater than 300,000 cycles under a flexural load of 850 MPa at 90° C.

Abstract: An acoustic structure that includes a honeycomb having cells in which septum caps are located. The septum caps are formed from sheets of acoustic material and include a resonator portion and a flange portion. The flange portion has an anchoring surface that provides frictional engagement of the septum caps to the honeycomb cells when the caps are inserted into the honeycomb during fabrication of the acoustic structure. An adhesive is applied to the anchoring surface of the septum caps after the caps have been inserted into the honeycomb cells to provide a permanent bond.

Abstract: Machinable composite molds for use in making a composite structure. The mold includes a mold body having a tool surface that is shaped to provide the molded surface of the composite structure. The mold body is made up of at least one mold layer composed of a quasi-isotropic material composed of a plurality of randomly oriented fiber bundles or chips impregnated with a resin. The use of randomly oriented fiber chips allows post-cure machining of the mold body.

Abstract: Core-skin bonding is improved between honeycomb and composite face sheets by applying a nylon-based (polyamide) adhesive to the edge of the honeycomb prior to bonding. Edge coating of honeycomb with polyamide adhesives is useful in further increasing the bond strength between honeycomb and prepreg face sheets, especially when the matrix resin of the prepreg is designed to adhere the prepreg to the honeycomb.

Abstract: An acoustic structure that includes a honeycomb having cells in which septum caps are located. The septum caps are formed from sheets of acoustic material and include a resonator portion and a flange portion. The flange portion has an anchoring surface that provides frictional engagement of the septum caps to the honeycomb cells when the caps are inserted into the honeycomb during fabrication of the acoustic structure. An adhesive is applied to the anchoring surface of the septum caps after the caps have been inserted into the honeycomb cells to provide a permanent bond.

Abstract: An uncured composite product having a middle fibrous reinforcement, a thermosetting-resin based layer and a hardening-agent based layer for the thermosetting resin. The thermosetting-resin based layer is placed on one side of the fibrous reinforcement and the hardening-agent based layer is placed on the other side so that the fibrous reinforcement forms a physical barrier between the thermosetting resin and the hardener. When heated, the thermosetting resin and/or hardener flows across the physical barrier to provide mixing and resultant curing.

Abstract: Moulding 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: The flow of resin during the molding of composite articles is controlled by forming areas of immobilized resin during the infusion of resin into the fibrous body. The immobilized resin is formed using an immobilization agent that interacts with the infused resin to form a high viscosity resin barrier that is effective in blocking the flow of non-immobilized resin. The barriers of immobilized resin are located within the fibrous body so as to control the flow of non-immobilized resin during the molding process to prevent or least reduce resin depletion and to selectively block resin flow from the mold.

Abstract: Process and system for fabricating a multidirectional fibrous reinforcement designed to be a porous preform for producing a part made of a composite material. Reinforcing thread is deposited in successive layers on a support surface. A binder is provided in association with the reinforcing thread so as to adhere the reinforcing thread to the support surface and the successive layers of thread. The reinforcing thread is pressed against the support surface in a manner that exerts a pressure substantially perpendicular to the support surface at the point where the thread is deposited. The binder may be pre-applied to the support surface or it can be applied simultaneously with the reinforcement thread.

Abstract: Panel assemblies that include a core sandwiched between face sheets made from composite material. A pigmented topcoat layer is applied directly to the composite material without the need for a separate adhesive. The pigmented topcoat layer includes a thermoplastic binder resin/pigment mixture that can be cured with the composite material in a single step. The topcoat may include permanent and/or temporary substrates for carrying the binder resin/pigment mixture and for providing a surface finish to the panel assembly.

Abstract: A fibrous reinforcement including a fibrous support treated throughout or covered at least partially on one of its surfaces with a compound containing: i) one or more thermosetting prepolymers having a softening temperature of 150° C. or lower and/or one or more thermoplastic polymers having a glass transition temperature lower than 300° C.; and ii) one or more inorganic phosphorus compounds. The treatment ratio of the fibrous support with the inorganic phosphorus compound(s) falls within the range of 2%–20% by weight. The fibrous reinforcement is suitable for use as a fireproofing agent.

Abstract: Heat-settable epoxy resin mixtures are provided that can be used alone or in combination with fibers to form large composite material structures without the need for high consolidation pressures. The heat-settable resin mixture is composed of a resin component, curing agent component and a particulate component. The particulate component includes rigid-rod polymer particles that dissolve when the heat-settable resin is heated to temperatures within a predetermined processing window. After heating to the processing temperature, the resulting heat-set resin is cooled to form a curable solid resin. The curable solid resin may be stored indefinitely or re-heated to curing temperatures to form a cured product.

Abstract: A method for making an amine-terminated polyarylene polyether thermoplastic in which a liquid/solid slurry reaction mixture is formed in an oxygen-free atmosphere. The reaction mixture is composed of a dihydroxyaromatic compound, a dihaloaromatic compound, an amino-hydroxyaromatic compound, a weak base, an aprotic polar solvent and a non-aromatic azeotrope former which is substantially imiscible with the aprotic polar solvent, said azeotrope former consisting of a molecule which has from 6 to 10 carbon atoms. The reaction mixture is refluxed at an elevated temperature to eventually produce a solution of the amine-terminated polyarylene polyether in the polar solvent. The method is designed for use in producing large amounts of thermoplastic in a simple, efficient and reliable manner.

Abstract: A fire resistant laminate for application to a core structure (12) to form a sandwich panel (10) having fire resistant face sheets (14 & 16). The laminate includes a fire protection (18) in which at least one layer of fibers (22) is embedded within a cured inorganic polymer matrix (24). The laminate further includes an adhesive layer (20) for bonding to the core structure.

Abstract: Resins which are a combination of phenolic and polyamide polymers are used as dipping resins to coat composite honeycomb structures. The phenolic/polyamide dipping resins increase the heat formability of composite honeycomb structures. The dip resin forms a coating on the honeycomb which includes from 30 to 95 weight percent phenolic resin and 5 to 30 weight percent polyamide resin. The dip resin is especially useful for coating composite honeycomb cores made from graphite or glass fibers impregnated with flexible phenolic resins.

Abstract: The crush properties of honeycomb are modified and controlled by providing crush control surfaces at the intersections of the honeycomb cell wall. The crush control surfaces form openings through the cell walls at the intersections which provide a reduction in crush strength of the honeycomb cell. A wide variety of crush properties for a given honeycomb may be accurately achieved by varying the size, shape, number and location of the crush control surfaces within the honeycomb.

Abstract: A method of producing a curable prepreg which comprises (i) sandwiching a multi-ply fabric layer comprising at least two superposed sheets of woven reinforcing fabric between solid films of a curable resin composition and (ii) heating the resulting sandwich under pressure so that the resin composition impregnates the sheets of woven reinforcing fabric to form a coherent curable structure.

Abstract: Heavy density honeycomb structures which include alternating layers of primary corrugated sheets and bisector sheets which are bonded together. The primary corrugated sheets are offset so that the bisector sheets are bonded to the corrugated sheet nodes so that the upper and lower bonding locations on each bisector sheet are displaced from each other. This displacement provides flexibility regions in the bisector sheets which enhance the formability of the heavy density honeycomb. The displaced node configuration is useful for enhancing thermal formability of both metallic and non-metallic honeycomb structures. The offset configuration is used with both substantially flat bisector sheets and corrugated bisector sheets.

Abstract: Expanded cellular structures are formed from dense nonporous cellulose paper with an air permeance of less than 30 ml/min which cellular structure is provided with a shape retention of at least 90%. The shape stability is obtained by forming the cellular structure, spraying with an aqueous liquid and heating, the amount of liquid, time and temperature of heating being selected and sufficient to provide the desired shape retention. The minimum amount of water is at least 30 weight % of dry paper more usually at least 75% with minimum heating of 1 minute at 100° C.