Abstract: A process for the hot press moulding of moulded articles, such as the internal linings of motor vehicles or the like is described, in which planar blanks of tangled fibre mat fleece mixed with binders, using at least one mould, are permanently deformed in a multidimensional moulding process after evaporating on the mat fleece. A stabilizing support is introduced during the deformation process on at least one side between the shaping surface of the mould and the mat fleece. It is in the form of a fibrous sandwich layer which is substantially elongation-free in the surface direction at ambient temperature, but is plastically deformable within the hot press mould under the action of heat. With and/or immediately after the moulding process, said stabilization support becomes a substantially elongation-free, inflexible covering. The geometry of the flexible stabilizing support is to be made to coincide with that of the mat fleece blank to be deformed.

Abstract: Nylon cords having a yarn strength of not less than 12 g/d are subjected to a stretch heating treatment under specified conditions before the dipping and then dipped in a dipping solution having a particular composition, whereby the strength and adhesion force of the resulting dipped cords are considerably improved for use in large size tires.

Abstract: A warp-free laminate is produced by winding a first set of strands or filaments about a flat mandrel with a second set of strands being wound transverse to the first set. The two sets may be perpendicular to each other. The filaments are maintained under a controlled tension while being impregnated with a resin and during subsequent cure of the resin. In order to permit the formation of a warp-free product, the winding pattern is such that it forms a mirror image about a neutral axis or plane of symmetry. The winding pattern may be chosen to provide interstices in a predetermined pattern permitting punching out or high speed drilling of hole openings for subsequent printed circuit applications.

Abstract: A process for rapidly forming a flexible mold for finely detailed objects from a radiatively curable molding composition includes coating at least a portion of the surface of a three-dimensional object with a fluid molding composition. The coating is cured by exposing the fluid coating to radiative energy to form an elastic, flexible layer of cured molding composition on the object. The coating and curing steps can be repeated to build up the flexible mold until a predetermined minimum has been attained. The cured molding composition is removed from the object, and is suitable for immediate use as a mold to cast duplicate reproductions of the object.

Abstract: The decorative panel having an underlay or core layer and a decorative layer on one or both sides of the core. At least one of the two surfaces of at least the outermost layer of the panel comprises a synthetic resin of one or more radiation-polymerized components selected from unsaturated acrylates and methacrylates. This layer, when scratched, has a scratch resistance of at least 1.5 N and preferably 2 to 7 N (DIN 53 799, part 10). In the method for manufacturing the decorative panel, a liquid surface layer which includes the radiation-polymerizable components is applied onto an underlay and then polymerized by means of radiation. In a further step, the radiation-polymerized surface layer is pressed together with the underlay at an elevated temperature.

Abstract: A method of making molds which is easy, quick and can be accomplished at room temperatures and atmospheric pressures. The method includes applying at least one layer of gel to a male mandrel and curing at least one layer of polyester impregnated fabric to the gel layer. At least one layer of epoxy impregnated fabric is cured to the polyester impregnated fabric. At least one layer of plaster impregnated is cured to the epoxy impregnated fabric. At least one layer of epoxy impregnated fabric is cured to the plaster impregnated fabric. The resulting mold is removed from the male mandrel.

Abstract: An aqueous coating composition is provided for thermoplastic films comprising(i) from 1 to 10 weight percent based upon the total weight of the coating composition, of a sulfonated copolyester consisting essentially of the polyester condensation product of the following monomers or their polyester-forming equivalents:(A) about 65 to 95 mole percent of isophthalic acid;(B) about 0 to 30 mole percent of at least one aliphatic dicarboxylic acid of the formula HOOC(CH.sub.2)--.sub.n COOH, wherein n ranges from about 1-11;(C) about 5 to about 15 mole percent of at least one sulfomonomer containing an alkali metal sulfonate group attached to a dicarboxylic aromatic nucleus; and(D) stoichiometric quantities of about 100 mole percent of at least one copolymerizable aliphatic or cycloaliphatic alkylene glycol having about from 2 to 11 carbon atoms,(ii) from 0.

Abstract: A process for preparing reinforced thermoset articles of manufacture from a lofted composite sheet employed as a skeleton or preform which is impregnated with a thermoset resin composition and cured. A reinforced thermoset article of manufacture prepared from a lofted composite impregnated with a thermoset resin composition and cured is also provided.

Abstract: A process for producing an acoustic diaphragm of carbonaceous material including the steps of impregnating nonwoven fabric or woven fabric of carbon fiber having a high degree of elasticity with a thermosetting resin, thermally molding it into a diaphragm shape, calcining the shaped fabric in an inert gas atmosphere to obtain a porous carbon molding, heating the porous molding to a uniform temperature, and depositing vapor phase, thermally decomposed carbon upon a surface of the porous molding. The deposited carbon is generated by thermal decomposition of a hydrocarbon-containing material introduced together with a carrier gas. The process produces an acoustic diaphragm having a dense surface layer of carbonized fiber-carbonized thermosetting resin-thermally decomposed carbon, and a porous interior of carbonized fiber bonded together by carbonized resin and the thermally decomposed carbon.

Abstract: A carbonaceous cylindrical body including a composite body of a carbonized material of a thin paper-like supporting body having a strength ratio of lengthwise direction to widthwise direction of 2 to 10 and obtained by manufacturing a paper-like body so that its carbonizable fibers are oriented and a carbonaceous matrix having an optically isotropic structure under a polarizing microscope and which shows a carbon content of at least 85% by weight, an oxygen gas permeation coefficient of 10.sup.-2 to 10.sup.-7 cm.sup.2 /sec. under a partial pressure of oxygen of 1 atmosphere and a bulk density of from 1.4 to 1.9 g/cm.sup.3. A process for producing the carbonaceous cylindrical body is also provided.

Abstract: The adhesive strength of highly oriented, highmolecular polyolefin filaments for polar polymeric matrices is improved by subjecting the filaments to a corona treatment with a total irradiation dosage of ##EQU1## effected intermittently in several smaller dosages. The process is particularly suited for treating superstrong polyethylene fibers, and making reinforced materials while applying as matrix a polyester, polyamide or epoxy resin.

Abstract: The invention relates to a method of making pieces of furniture, more particularly arm-chairs and the like, starting from flat sheets of felt or the like, and comprising the following phases:preparation of a flat sheet formed by a felt or similar compressed material including or adapted to be associated with a hardening substance;punching of the flat sheet in a pattern corresponding to the flat lay-out of the piece of furniture to be produced, arranging all the incisions and holes required for the successive foldings and applications of its parts;possible softening of the hardening substance included in the felt or the impregnation of the felt with a hardening substance;shaping of the flat sheet to the final form of the piece of furniture to be obtained;hardening of the hardening substance in the zones which must be given the required rigidity, leaving the other zones in the natural state;assembly of any further parts of the piece of furniture for its completion;finishing treatments of the piece of furniture.

Abstract: Oral and extraoral prosthetic constructions of composite material with considerable fiber content, and in particular, jawbone anchored dental bridges of reinforced plastic, are made by the following method. A number of mutually retracted tubularly braided fibers (1), possibly in combination with continuous fiber strands, so-called roving, together constitute a fiber system which is packed in a tube, hose (2) or the like which is sealed and serves as outer packaging. A suitable matrix material, for example acrylic plastic, is injected into the hose for impregnation (wetting) of the enclosed fiber system, whereafter the hose (2) is removed. The fiber system is then polymerized to form a finished prosthesis blank in a mold. The prosthesis blank is then given suitable form and appearance by conventional after treatment.

Abstract: A novel isotropically reinforced microcomposite is described. An entirely fluid-phase method has been devised for producing the net-shape filamentary structures. The process depends for its success on the ability to generate in situ, within a shaped mold, a three-dimensional random weave of carbon filaments by catalytic decomposition of a hydrocarbon feed. Almost any desired filament filler matrix combination can be produced by utilizing chemical vapor deposition to modify the surface and bulk properties of the filamentary structure. Infiltration of filler matrix materials can be achieved by adaptation of existing materials technologies.

Abstract: A polyamide yarn having on the surface of the polyamide yarn a hydrophobic organic ester dip penetration regulator having a melting point greater than 27.degree. C. and convertible by conventional means into a tire cord having low stiffness and high air permeability and a process for making polymeric tire yarns is disclosed.

Abstract: A shaped article of fiber reinforced material is made by forming a foamed aqueous dispersion having single discrete fibers, and unconsolidated particulate thermoplastic or thermosetting material, laying down and draining the dispersion to form a web, transferring the web to an oven and heating it to form a self-sustaining permeable sheet, transferring the sheet to a through-air heating oven, passing heated air through the sheet to cause substantially uniform and homogeneous heating of the thermoplastic component, transferring the heated sheet to a compression mold, and subjecting the sheet to compression molding to form a shaped fiber reinforced plastic article.

Abstract: A method of molding a polymeric containing article by exposing the article to ultraviolet radiation and a substantially uniform pressure. The method includes placing the precursor article within a pressure vessel and substantially filling the vessel with a solid, flowable, polymer medium that is substantially ultraviolet transparent under pressure. The polymer medium is pressurized so as to produce a substantially, uniform predetermined pressure on the surface of the article and the article is exposed to ultraviolet radiation that passes through the polymer medium to cure the article. Alternatively, the polymeric article may be passed through the medium containing vessel during exposure to ultraviolet radiation and a substantially uniform pressure.

Abstract: A molding process of a molding compound containing an ingredient such as a binder, e.g., pitch or a thermosetting resin which generate gas before being set, is disclosed, wherein the molding compound is heated and molded under pressure according to a special temperature pattern. First, the molding compound may be preheated substantially uniformly to a temperature at which the binder melts and generates reaction gas. Next, temperature gradient in the direction of thickness of the molding is created while raising the temperature of the molding to an upper limit temperature so that the setting of the molding progressively advances from the higher temperature to the lower temperature side of the molding.

Abstract: A method of making high efficiency, flame resistant polyimide foam insulation particularly suitable for insulating plastic pipes and forming ducts. Typically a sheet of polyimide foam which has been foamed unconstrained is placed between opposed caul plates, squeezed to a thickness less than the original thickness and heated to stabilize the new sheet thickness. Face sheets coated with a polyimide adhesive can then be placed against the stabilized foam faces and heated between plates to bond the face sheets to the foam. Also, a sheet of foam which had been impregnated with polyimide resin precursor can be placed against the stabilized sheet and the resin precursor simultaneously cured and the sheet bonded to the stabilized foam. A variety of flat, tubular or other shapes can be made by this method. The resulting insulation panels, tubes or the like have greatly improved flame resistance and excellent thermal insulation characteristics.

Abstract: The present invention is a process for pultruding fiber reinforced phenolic resin products, in which the phenolic resin normally has a viscosity ranging from 3,000 to 5,000 cps at 25.degree. C. and is heated to maintain a viscosity ranging from 800 to 2,000 cps during the impregnating step. A die having a temperature profile which is particularly suitable for use in the present process is also disclosed, which has substantially three different heating temperatures along the pultrusion direction. Furthermore, a postcuring treatment for improving the mechanical and physical properties of the pultruded products is also disclosed in the present invention.

Abstract: Manufacture of a multifilament polyester yarn which is suitable for use as an industrial yarn, particularly tire yarn, and displays a specific breaking strength at high spinning speeds, the yarn is made in accordance with a process comprising the successive steps of spinning a molten polymer through a plurality of holes, cooling and drawing the resulting filaments, and finally collecting them, the polymer flow in each of the spinneret holes exhibits a core portion having a higher relative viscosity and a sheath portion having a lower relative viscosity, the difference between said relative viscosities amounting to less than 0.100, preferably 0.040-0.003.

Abstract: A device and method to prevent delamination at load-bearing apertures in structural composite substrates is disclosed. The device is a composite reinforcing grommet having a hollow, generally tubular member of braided filaments impregnated with polymer. The member may be radially deformed for insertion into an aperture in a structural composite substrate and is then capable of being radially expanded to form flanges to secure the structural composite between the flanges. A method of reinforcing a substrate having an aperture therethrough including the step of cobonding a composite reinforcing grommet to a structural composite substrate is also disclosed.

Abstract: Filament wound or dry lay-ups of structural shapes are impregnated with a binder of thermoplastic resin. Impregnation is achieve by adding a polymer solution to a centrifuge containing reinforcing material. The centrifuge is spun at high rotational speed. Solution is metered into the centrifuge and contacts the inner surface of the reinforicng material. A preheated carrier gas flow is circulated in the centrifuge using baffles, then released to a solvent recovery system. Alternatively, vacuum drying to recover solvent can be used.

Abstract: The present invention relates to a process for the preparation of a composite material wherein the element used to reinforce the composite material is subjected to an electrostatic field induced by a high voltage electric current, said element being then impregnated with a liquid matrix material or precursor of matrix, while still under the influence of said field, and to the composite materials obtained by carrying out said process, notably vulcanized products, in particular vehicle tires, ceramics and electrodes.

Abstract: A method of preparing carbon filaments which comprises exposing a suitable thermostable substrate which is covered with reduced monocrystalline metal particles with a diameter of at least 5 nanometers to a carbon containing gas mixture at temperatures of about 250.degree. up to about 700.degree. C. to 800.degree. C., for a period of time sufficient to form filaments of the desired length, and thereafter removing the substrate and/or the metal particles. The filaments are characterized by a crystalline graphitic structure and a morphology defined by a fishbone-like arrangement of the graphite layers along the axis of the filaments. A high carbide content is a prerequisite for the nucleation of the filamentous carbon with a fishbone like structure.

Abstract: A method of molding oriented structural yarn/polymer matrix composite structural articles in which a preform of oriented yarn layers saturated with a resin is placed in a shape-defining mold, which is put in an enclosure, and subjected to heat and pressure to cure the resin, after which a cooling medium may be introduced. To enable the use of lightweight multi-part molds, and a mixture of pressure is distributed evenly, an internal liner is collapsed about the mold prior to curing. The process is extremely productive, and allows for accuracy and reproducibility through the use of real time temperature monitoring and closed loop feedback control.

Abstract: An epoxy resin system is disclosed which is especially adapted for use in the pultrusion process. Such resin system comprises tris (hydroxyphenyl) methane-based epoxy resin and a combination of the cross-linking agents (methyl)-bicyclo(2,2,1) heptane-2,3-dicarboxylic anhydride and poly sebacic poly anhydride, the ratio of the dicarboxylic anhydride to the total amount of cross-linking agents ranging from 0.65 to 0.80 and the ratio of the poly anhydride to the total amount of cross-linking agents ranging from 0.35 to 0.20. The amount of total cross-linking agents to epoxy resin ranges from about 60 to about 80 parts total cross-linking agents, per 100 parts resin, by weight. A small amount of an imidazole accelerator, preferably 2-ethyl-4 methyl imidazole, is included.

Abstract: A process for preparing a molded product of thermochromic polyvinyl chloride characterized by incorporating a thermochromic particulate material into a vinyl chloride plastisol comprising a vinyl chloride resin, plasticizer, stabilizer, lubricant and filler, and molding the resulting mixture. The thermochromic particulate material is prepared from particles of a non-thermoplastic resin having encapusated therein the three components of electron-donating chromogenic substance, electron-accepting substance and solvent by coating the particles with a hydrophilic high-molecular-weight compound.

Abstract: The formation of structural composites having low smoke release and low heat release properties by forming a sandwich comprising a non-woven fiber mat between woven glass fiber mats and impregnating said sandwich with a mixture of a bisoxazoline and a polyphenolic compound to form a prepreg which can be formed and molded at elevated temperatures is described.

Abstract: A process for producing a lining member, particularly a covering member, in which a fibrous material in single or multiple layer form is located with a binder preferably comprising a thermosettable polyester resin. Preferably a foam plate support layer is positioned at least on one side of the fibrous material which has been coated with a binder and such is preferably covered with a non-woven fabric layer. The assembly is compressed in a molding press. A ultrafine glass fiber non-woven fabric is used as the fibrous material layer.

Abstract: A method and apparatus for making a charge used in molding a fiber reinforced part. Continuous strands of fibers are impregnated with resin and then cut into segments of predetermined lengths. The segments are collected so that the resin impregnated fiber segments are piled together to form the charge. In one embodiment, the fibers are collected in a controlled manner to provide preselected fiber orientation for the molded part. Also a cutter mechanism is provided for cutting resin impregnated fiber strands pulled over a first rotating drum.

Abstract: A process (I), for producing a pressure-sensitive electroconductive sheet by (A), forming conductive circuits or electrodes in a flexible porous substrate and (B), applying, followed by curing a pressure-sensitive conductive paste to either or both sides of the substrate to form a pressure-sensitive conductive layer; and a process (II) for producing a pressure-sensitive electroconductive sheet by (A), forming conductive circuits or electrodes in a flexible porous subhstrate, (B), subsequently applying, followed by curing, a pressure-sensitive conductive paste to either side of the substrate to form a pressure-sensitive conductive layer, and (C), applying, followed by curing, insulating silicone rubber to the side of the substrate on which the pressure-sensitive conductive layer is not formed to form an insulating silicone rubber layer.

Abstract: A method for manufacturing a concrete structure such as columns and beams with sufficient reinforcement in the shear strength to be durable against earthquakes, etc. A reinforcing member composed of a fiber-reinforced plastic is applied onto the outer periphery of a concrete structural member by winding the fiber strands around the outer periphery of the concrete structural member while impregnating the fiber material with a resin.

Abstract: A method of making structural panels having a controlled density polyimide core, generally with at least one face sheet. An open cell polyimide foam panel is impregnated with a liquid polyimide precursor, compressed to squeeze out all but a desired quantity of the polyimide precursor and dried. One or two face sheets are impregnated with the same liquid polyimide precursor and placed on one or both faces of the foam panel, with pre-drying of the face sheet if desired. This assembly is placed in a mold and subjected to slight compression. The assembly is heated to a moderate temperature for a suitable time to take on the mold configuration. Then the assembly is heated to the curing temperature of the polyimide precursor for a period sufficient to cause curing. The resulting structural panel has a selected density, which determines strength and rigidity, weight and other physical characteristics, controlled by the amount of precursor allowed to remain after the impregnation foam compression step.

Abstract: A method and apparatus are disclosed for the fabrication of pultruded articles. The apparatus includes a means for heating the interior of a bundle of resin-wetted reinforcing material prior to the bundle passing into a heating forming die which heats the exterior of the bundle. Insertion of a thermocouple wire into the interior of the bundle prior to the bundle passing into the heated forming die allows the temperature of the bundle interior to be monitored during the curing process that occurs within the heating forming die. Adjustment of the bundle interior temperature relative to the bundle exterior temperature eliminates stresses caused by adverse thermal gradients that normally would exist without the use of such a bundle interior heater. Use of such a bundle interior heater allows the pultrusion of parts having a greater or thicker cross section than those now normally available.

Abstract: A flexible rubber boot that transmits molding pressure to the inner surface of the structure to be molded is placed on a support fixture. The boot is held in place by a vacuum applied between the fixture and the boot. Prepregs are laid up on the boot to the desired depth and in a desired configuration. A female mold assembly, consisting of two sections, is then placed over the prepreg material and sealed to the boot. A vacuum is applied to the sealed region between the mold and boot, compressing the material against the interior of the mold that defines the outer surface of the structure. The assembly of boot, mold, and material is then placed in an autoclave. After the material has cured, the finished structure is separated from the mold and boot. The tooling is reusable and the process completed easily, allowing the efficient fabrication of structure having smooth inner and outer surfaces.

Abstract: A fastener member and method of formation are provided wherein a bolt and nut are formed from a block of resin-impregnated fibers woven in a first, second and third plane each perpendicular to the other wherein the fibers in the first plane extend continuously and longitudinally through the fastener member and the fibers in the second and third plane extend to form the peaks and valleys of the helical thread.

Abstract: A method of forming a fiber-reinforced, glass or glass-ceramic, elongated composite is described wherein several multifiber lengths are impregnated with matrix material, woven or twisted to form a fabric network, the impregnating matrix material softened, and the network subjected to a stretching action along the central axis of the fiber network to collapse the network and consolidate it to a solid composite.

Abstract: Coated, reinforced composites are prepared by a process in which(i) a liquid composition comprising a photocurable residue and a residue having at least one epoxide group or phenolic hydroxyl group is applied to the surface of a mould,(ii) the composition is exposed to actinic radiation until it solidifies,(iii) reinforcement and a thermosettable composition are applied to the solidified layer, this composition containing an epoxide resin or a phenolic resin,(iv) the assembly is heated to form a cured moulding, and(v) the moulding is removed from the mould.

Abstract: In order to achieve defined fiber orientation angles in the fiber-reinforced plastic material of a hollow shaft, consisting of such material, the hollow shaft having regions of different diameters, a braided fiber tube constituting the starting material is pulled over a core, is impregnated with settable plastic, and is hardened.

Abstract: In a method and apparatus for continuous shaping of carbon-fiber-reinforced plastic tubes, a carbon fiber prepreg in tape form impregnated with a first thermosetting resin is laminated on and around a mandrel; the laminate provided on said mandrel is preheated; and the preheated laminate is pulled in and through a hot die together with the mandrel, during which it is gelled, cured, and shaped into a carbon-fiber-reinforced plastic tube, wherein a second thermosetting resin is uniformly supplied onto the outer circumference of the laminate in a resin squeezing zone in the hot die.

Abstract: A method of continuous molding a rod-like product includes forming an uncured rod-like molding by passing reinforcing fibers impregnated with uncured thermosetting resin through a squeezing die having a predetermined shape. Molten thermoplastic fluororesin is extruded in a ring shape to enclose the rod-like molding. A sheathing layer of the thermoplastic resin is formed by causing the thermoplastic resin to come into contact with the outer periphery of the uncured rod-like molding and by cooling and solidifying the thermoplastic resin. The uncured rod-like molding and the sheathing layer are introduced into a heated tank thereby hardening the thermosetting resin. The sheathing layer is stripped from the molding to form a rod-like product having a surface of fiber reinforced thermosetting resin.

Abstract: A process relating to the manufacturing of a structural reinforcing material which is made of a glass fiber reinforced plastic, a carbon fiber reinforced plastic or similar material wherein a precise sectional shape is not required. A fiber body including a plurality of reinforcing fibers is impregnated with a hardenable material and subsequently introduced into a drawing die having a desired sectional shape so as to be formed into a drawn article having a predetermined sectional shape. A tape is coiled therearound so as to cover the article. A string member is coiled therearound to thrust into the surface of the article. Thereafter, the drawn fiber body is subjected to a hardening treatment and the tape and string member are removed.

Abstract: A rigid, non-metallic laminate suitable as a fire barrier, made by impregnating a layer of non-metallic fibers other than glass fibers with a resin, coating glass fibers with a refractory aluminum silicate to form a sheath, superimposing a layer of the thus alumina silicate coated glass fibers on the resin impregnated layer of non-metallic fibers and then subjecting the resulting laminate simultaneously to heat and pressure to squeeze resin from the non-metallic fibers into the interstices of the alumina silicate coated glass fibers and to cure the resin binder. A rigid multi-layer laminate in a common resin binder useful as a fire resistant panel or duct for a gas turbine engine results.

Abstract: The method comprises placing upper and lower stacks of unimpregnated fibrous reinforcement plies having a core of preimpregnated fibrous reinforcement plies therebetween in a mold and injecting chemically activated resin to impregnate the upper and lower stacks of unimpregnated fibrous reinforcement plies and initiate curing of heat-activatable resin of the core, and removing the molded part from the mold after curing and cooling of the part.

Abstract: Fiber reinforced molding compounds wherein the resinous matrix is a thermosetting linear polymer characterized in constituting two oligomeric ethylenically unsaturated polyester segments joined through a polyurethane residue and having acryloyl or methacryloyl end groups.

Abstract: A constant cross-sectional area filament wound composite material leaf spring of optimal energy storage efficiency given the constraints of filament winding and maximum spring width comprises a portion which widens toward the end of the spring, the rate of increase of width of the spring being such that the longitudinal side surfaces of the spring along such portions follow a lateral, outwardly convex curve of radius R.sub.I, wherein R.sub.I at each point is substantially equal to the camber, i.e., the longitudinal radius of curvature R.sub.C at that point.

Abstract: A method of producing a continuous fiber reinforced bent resin pipe, including winding a continuous reinforcing fiber on the outer surface of a tube-like flexible core mold while such core mold is straight in shape, the flexible core mold which is straight when unloaded being capable of keeping a cross section defined in radial direction when the core mold is bent. The core mold on which the continuous fiber has been wound is then bent and placed into a cavity defined by an outer mold formed of split molds each having an inner surface forming the predetermined outer configuration of a bent pipe. A liquefied synthetic resin is caused to be cured between the outer and the core molds to integrate both the fiber and resin. Thereafter the molded product is removed from the outer mold and the core mold is removed from the molded product.

Abstract: A roving laid flat of unitary metal, mineral or synthetic filaments is treated with a powder, whose grain size is equal to the diameter of the filaments, of a plastic material chosen either from the group of thermosetting polyers including the epoxides, the phenolics, the polyesters with terminal groups --COOH, the polyimides, the acrylics and the polyurethanes, or prepolymerized polyamides modified by diamines, polyolefins modified by maleic anhydride or acrylic acid, partially hydrolized EVA copolymers, the E-VA-maleic anhydride terpolymers and eva copolymers grafted by the acrylic radical, then the powder charged rovings are coated by a thermoplastic polymer, such as polyamides, copolyamides and linear polyesters, the material thus obtained being placed in a mold under pressure and at a temperature not exceeding 170.degree. C.

Abstract: Rigidized composite preforms are fabricated by first serving individual reinforcement strands with a thread of a thermoplastic material. After shaping the reinforcement strands into a desired geometry, the shaped strands are heated to melt the thermoplastic threads. By then cooling the shaped reinforcement strands, the thermoplastic material solidifies and acts as an adhesive or glue in holding the preform together in a rigid fashion. Such rigid preforms are particularly suitable for handling, storage and transportation to other locations and media prior to densification. Densification may be performed by conventional techniques to produce the final composite article. Pyrolysis of the matrices and subsequent densification of the matrix may be accomplished.