Treating an uncured resin matrix composition to impart energy to the resin matrix composition enables a stable Tg to be achieved whereby the resin matrix composition may be stored and has a low tack enabling subsequent processing and handling. The invention provides a method of achieving a stable Tg without the resin matrix composition starting to cure and a method of determining the treatment regime by which a resin matrix composition with a stable Tg may be obtained. The resin matrix composition may be fresh or reused uncured resin matrix composition and may contain fibrous reinforcement.
A reinforcing composite comprising a plurality of layers of reinforcing composite material forming a stack wherein at least one layer of the stack comprises a moulding compound (114) comprising consolidated resin impregnated fiber elements, wherein the resin impregnated fiber elements are obtained from off-cuts or scrap material (112) derived from cutting single layers of reinforcing composite material and/or stacks comprising multiple layers of reinforcing composite material (110).
B29C 70/08 - Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, with or without non-reinforced layers
B29B 17/00 - Recovery of plastics or other constituents of waste material containing plastics
B29C 70/54 - Component parts, details or accessoriesAuxiliary operations
B29C 70/46 - Shaping or impregnating by compression for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
B29C 70/14 - Fibrous reinforcements only characterised by the structure of fibrous reinforcements using fibres of short length, e.g. in the form of a mat oriented
B29K 105/08 - Condition, form or state of moulded material containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns
B29K 63/00 - Use of epoxy resins as moulding material
A mould for the production of articles comprising a cavity for the retention of a fibrous material impregnated with a curable resin defined by a top, a base (1) and side walls (4, 5, 6, 7) and an internal insert (2) having sectional walls that can move independently of each other in order to exert pressure on the fibrous material.
B29C 70/46 - Shaping or impregnating by compression for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
B29C 33/44 - Moulds or coresDetails thereof or accessories therefor with means for, or specially constructed to facilitate, the removal of articles, e.g. of undercut articles
B29C 70/12 - Fibrous reinforcements only characterised by the structure of fibrous reinforcements using fibres of short length, e.g. in the form of a mat
B29K 63/00 - Use of epoxy resins as moulding material
B29K 79/00 - Use of other polymers having nitrogen, with or without oxygen or carbon only, in the main chain, as moulding material
B29K 105/08 - Condition, form or state of moulded material containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns
B29K 105/10 - Condition, form or state of moulded material containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns oriented
A method of separating a composite material stack comprising multiple elements (12) in contact with one another is discloses. Each element (12) comprises reinforcement fibers and an uncured resin matrix, and the method comprises the steps of temperature treating the stack and/or applying a stress to the stack to separate the elements.
B29C 70/54 - Component parts, details or accessoriesAuxiliary operations
B29C 70/50 - Shaping or impregnating by compression for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
B29B 13/04 - Conditioning or physical treatment of the material to be shaped by cooling
Treating an uncured resin to impart energy to the resin enables a stable Tg to be achieved whereby the resin may be stored and has a low tack enabling subsequent processing and handling. The invention provides a method of achieving a stable Tg without the resin starting to cure and a method of determining the treatment regime by which a resin with a stable Tg may be obtained. The resin may be fresh or reused uncured resin and may contain fibrous reinforcement.
Treating an uncured resin matrix composition to impart energy to the resin matrix composition enables a stable Tg to be achieved whereby the resin matrix composition may be stored and has a low tack enabling subsequent processing and handling. The invention provides a method of achieving a stable Tg without the resin matrix composition starting to cure and a method of determining the treatment regime by which a resin matrix composition with a stable Tg may be obtained. The resin matrix composition may be fresh or reused uncured resin matrix composition and may contain fibrous reinforcement.
A reinforcing composite comprising a plurality of layers of reinforcing composite material forming a stack wherein at least one layer of the stack comprises a moulding compound (114) comprising consolidated resin impregnated fiber elements, wherein the resin impregnated fiber elements are obtained from off-cuts or scrap material (112) derived from cutting single layers of reinforcing composite material and/or stacks comprising multiple layers of reinforcing composite material (110).
B29C 70/08 - Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, with or without non-reinforced layers
B29C 70/14 - Fibrous reinforcements only characterised by the structure of fibrous reinforcements using fibres of short length, e.g. in the form of a mat oriented
B29C 70/46 - Shaping or impregnating by compression for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
B29C 70/54 - Component parts, details or accessoriesAuxiliary operations
B29B 17/00 - Recovery of plastics or other constituents of waste material containing plastics
B29C 43/00 - Compression moulding, i.e. applying external pressure to flow the moulding materialApparatus therefor
8.
IMPROVEMENTS IN OR RELATING TO FIBRE REINFORCED COMPOSITES
The invention relates to a reinforcing composite comprising a plurality of layers of reinforcing composite material forming a stack wherein the number of layers and/or orientation of composite material that are employed at locations within the stack that are subject to elevated in-use stress in comparison with other locations within the stack according to an in-use stress evaluation of the stack, is increased with additional layers of composite material which are provided at the increased in-use stress locations.
B29C 70/86 - Incorporating in coherent impregnated reinforcing layers
B29C 70/30 - Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or coreShaping by spray-up, i.e. spraying of fibres on a mould, former or core
B29L 31/30 - Vehicles, e.g. ships or aircraft, or body parts thereof
This invention relates to a process for the production of a fibrous material embedded in a matrix of liquid or semi solid curable resin. The process comprises the steps of applying the resin to a continuously moving web of the fibrous material and subjecting the moving web with the resin applied thereto to ultrasound.
A method of separating a composite material stack comprising multiple elements (12) in contact with one another is discloses. Each element (12) comprises reinforcement fibers and an uncured resin matrix, and the method comprises the steps of temperature treating the stack and/or applying a stress to the stack to separate the elements.
B29C 70/50 - Shaping or impregnating by compression for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
Mechanically attaching articles made from composites has problems due to the difference in properties of the composite in the x, y planar direction and the z perpendicular direction, this results in different properties between the composite and the attachment member such as differences in coefficients of thermal expansion which can weaken the joint further leading to differences in moisture uptake which can further reduce the strength and robustness of the joint. The invention relates to the selection of the position of a joint in order to reduce such problems and to operating the moulding process in a way that improves the provision of mechanical attachments such as bolt holes.
B29C 65/56 - Joining of preformed partsApparatus therefor using mechanical means
B29C 65/48 - Joining of preformed partsApparatus therefor using adhesives
B29C 65/00 - Joining of preformed partsApparatus therefor
B29C 70/22 - Fibrous reinforcements only characterised by the structure of fibrous reinforcements using fibres of substantial or continuous length oriented in at least two directions forming a two dimensional structure
B29C 70/54 - Component parts, details or accessoriesAuxiliary operations
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.
B32B 5/02 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by structural features of a layer comprising fibres or filaments
B32B 3/12 - Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shapeLayered products comprising a layer having particular features of form characterised by a discontinuous layer, i.e. apertured or formed of separate pieces of material characterised by a layer of regularly-arranged cells whether integral or formed individually or by conjunction of separate strips, e.g. honeycomb structure
B32B 5/26 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by the presence of two or more layers which comprise fibres, filaments, granules, or powder, or are foamed or specifically porous one layer being a fibrous or filamentary layer another layer also being fibrous or filamentary
B64C 1/00 - FuselagesConstructional features common to fuselages, wings, stabilising surfaces or the like
13.
Process for prolonging the processing window of thermosetting resins
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.
B29C 45/14 - Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mouldApparatus therefor incorporating preformed parts or layers, e.g. injection moulding around inserts or for coating articles
14.
SANDWICH PANELS FOR AEROSPACE STRUCTURAL APPLICATION
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.
B32B 3/12 - Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shapeLayered products comprising a layer having particular features of form characterised by a discontinuous layer, i.e. apertured or formed of separate pieces of material characterised by a layer of regularly-arranged cells whether integral or formed individually or by conjunction of separate strips, e.g. honeycomb structure
B64C 1/00 - FuselagesConstructional features common to fuselages, wings, stabilising surfaces or the like
B32B 5/26 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by the presence of two or more layers which comprise fibres, filaments, granules, or powder, or are foamed or specifically porous one layer being a fibrous or filamentary layer another layer also being fibrous or filamentary
B32B 5/02 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by structural features of a layer comprising fibres or filaments
15.
PROCESS FOR PROLONGING THE PROCESSING WINDOW OF THERMOSETTING RESINS
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.
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.
patents
