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Moulding resins and u.v.-transparent moulds made from the resins for making fibre reinforced articles
Abstracts of Patents The block copolymer has the form AB or ABA and may contain small amounts of A(BA),, where n is between 2 and 5. A is an unsaturated polyester and B is a flexible polymer with a Tg of 0°C or less. The fibre structure makes up 5-85 wt% of the composite.
Ceramics composite material and production thereof Garvie, G.H. (Commonwealth Scientific and Industrial Research Organisation, Campbell, Australia) US Pat 5 334 563 (2 August 1994) A composite comprising 5-90 vol% alumina matrix and l ~ 0 vol% dispersed particles composed of strongly bonded agglomerates of microcrystals of monoclinic zirconia. The alumina grains are between 15 and 80 ~ in size and the size of the zirconia particles is such that cracks are not formed in the agglomerates on cooling from 1600°C to room temperature.
PROCESSES
Method for improving the mechanical performance of composite articles Gomez, J.A., Magrum, G.R., Pohl, E.R., Osterholtz, F.D., Sweeney, J.B., Adzima, L.J., Flautt, M.C. and Krumlauf, P.R. (Union Carbide Chemicals and Plastics Corporation, Danbury, CT and OwensCorning Fiberglass Technology, Inc., Toledo, OH, both of USA) US Pat 5 319 003 (7 June 1994) Continuous filaments are coated with a thermosetting mixture composed of a resin, a styrene monomer and a thermoplastic polyvinylacetate homopolymer. The coated filaments are subjected to a filament winding or protrusion treatment to form them into the desired shape after which they are cured. The resin may be a polyester resin, a vinyl ester resin or a mixture of these.
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Method of forming a preform by precoating glass fibres prior to chopping and preforming Kelman, J. and Hames, R. (Davidson Textron Inc., Dover, NH, USA) USPat 5 328 494 (12 July 1994) Unchopped glass fibre roving is coated by passing it through a tank of liquefied thermoplastic binder and the coating is solidified by cooling. The fibre is then chopped and passed into a gas flow so that the chopped fibres are blown onto a preform screen, where they are retained. Finally the resultant preform is heat cured. Process for producing inorganic fibre-based prepreg sheet and process for producing insulating laminate Yokoyama, H., Toyoshima, S. and Ibaraki, T. (Honshu Paper Co., Ltd, Tokyo, Japan) US Pat 5 328 566 (12 July 1994) A prepreg sheet is prepared by forming a slurry containing 35-80 wt% phenolic resin powder, the particles of which have an average diameter of 0.01-100 }am, and 2 ~ 6 5 wt% inorganic fibres, and which contains a nonionic high molecular weight fixing agent. The slurry is formed into a sheet and a silane coupling agent applied. Moulding resins and u.v.-transparent moulds made from the resins for making fibre reinforced articles Boeckeler, R.H. (Cook Composites and Polymers Co., Port Washington, WT, USA) US Pat 5 332 536 (26 July 1994) Reinforcing fibres coated with a composition containing a photohardenable material which is polymerizable under u.v. and a polymerization photoinitiator are applied onto a preform mould surface. The whole is then exposed to u.v. light, which passes through the mould surface, to form a solid prepreg. The mould surface consists of a heat cured casting of a liquid moulding resin comprising at least 25 wt% of a urethane acrylate, at least 10 wt% of an alpha, beta-ethylenically
COMPOSITES Volume 26 Number 7 1995
unsaturated monomer and a amount of a peroxide initiator.
catalytic
Refractory oxycompoundlrefractory hard metal composite Duruz, J.-J. (Moltech Invent SA, Luxembourg) US Pat 5 332 540 (26 July 1994) Particles of Ti, Zr, Hf, V, Nb or Ta borides are distributed in a mould and molten alumina or a molten refractory oxycompound of aluminium is cast around the particles to form a solid composite block. The resultant composite is aluminium wettable. Superstrength metal composite material and process for making the same Louat, N.P., Provenzano, V., Imam, M.A. and Sadananda, K. (Secretary State of the Navy, Washington, DC, USA) US Pat 5 333 667 (2 August 1994) Particles with an average size of less than 1 }am are placed inside a hollow cylinder composed of a metallic matrix material. The particles have a lower ductility than the cylinder but a higher melting point. The cylinder is capped with the matrix material and the whole is wrapped in a foil which has higher melting point than either the particles or the matrix. The foil wrapped cylinder is placed in a jacket which is then evacuated and hot pressed isostatically at a temperature between the melting points of the matrix and the particles to produce a metal matrix composite composed of the particles embedded in the matrix material. Process for coating carbon fibres with pitch and composites made therefrom Edie, D.D. and Klett, J.W. (Clemson University, Clemson, SC, USA) US Pat 5 334 414 (2 August 1994) Carbon fibres are passed through a pressurized air comb spreader to form a spread tow on which pitch is deposited such that it coats the individual filaments. The coated tow is formed into a carbon/carbon composite by carbonization.
Ceramics composite material and production thereof Garvie, G.H. (Commonwealth Scientific and Industrial Research Organisation, Campbell, Australia) US Pat 5 334 563 (2 August 1994) A composite comprising 5-90 vol% alumina matrix and l ~ 0 vol% dispersed particles composed of strongly bonded agglomerates of microcrystals of monoclinic zirconia. The alumina grains are between 15 and 80 ~ in size and the size of the zirconia particles is such that cracks are not formed in the agglomerates on cooling from 1600°C to room temperature.
PROCESSES
Method for improving the mechanical performance of composite articles Gomez, J.A., Magrum, G.R., Pohl, E.R., Osterholtz, F.D., Sweeney, J.B., Adzima, L.J., Flautt, M.C. and Krumlauf, P.R. (Union Carbide Chemicals and Plastics Corporation, Danbury, CT and OwensCorning Fiberglass Technology, Inc., Toledo, OH, both of USA) US Pat 5 319 003 (7 June 1994) Continuous filaments are coated with a thermosetting mixture composed of a resin, a styrene monomer and a thermoplastic polyvinylacetate homopolymer. The coated filaments are subjected to a filament winding or protrusion treatment to form them into the desired shape after which they are cured. The resin may be a polyester resin, a vinyl ester resin or a mixture of these.
526
Method of forming a preform by precoating glass fibres prior to chopping and preforming Kelman, J. and Hames, R. (Davidson Textron Inc., Dover, NH, USA) USPat 5 328 494 (12 July 1994) Unchopped glass fibre roving is coated by passing it through a tank of liquefied thermoplastic binder and the coating is solidified by cooling. The fibre is then chopped and passed into a gas flow so that the chopped fibres are blown onto a preform screen, where they are retained. Finally the resultant preform is heat cured. Process for producing inorganic fibre-based prepreg sheet and process for producing insulating laminate Yokoyama, H., Toyoshima, S. and Ibaraki, T. (Honshu Paper Co., Ltd, Tokyo, Japan) US Pat 5 328 566 (12 July 1994) A prepreg sheet is prepared by forming a slurry containing 35-80 wt% phenolic resin powder, the particles of which have an average diameter of 0.01-100 }am, and 2 ~ 6 5 wt% inorganic fibres, and which contains a nonionic high molecular weight fixing agent. The slurry is formed into a sheet and a silane coupling agent applied. Moulding resins and u.v.-transparent moulds made from the resins for making fibre reinforced articles Boeckeler, R.H. (Cook Composites and Polymers Co., Port Washington, WT, USA) US Pat 5 332 536 (26 July 1994) Reinforcing fibres coated with a composition containing a photohardenable material which is polymerizable under u.v. and a polymerization photoinitiator are applied onto a preform mould surface. The whole is then exposed to u.v. light, which passes through the mould surface, to form a solid prepreg. The mould surface consists of a heat cured casting of a liquid moulding resin comprising at least 25 wt% of a urethane acrylate, at least 10 wt% of an alpha, beta-ethylenically
COMPOSITES Volume 26 Number 7 1995
unsaturated monomer and a amount of a peroxide initiator.
catalytic
Refractory oxycompoundlrefractory hard metal composite Duruz, J.-J. (Moltech Invent SA, Luxembourg) US Pat 5 332 540 (26 July 1994) Particles of Ti, Zr, Hf, V, Nb or Ta borides are distributed in a mould and molten alumina or a molten refractory oxycompound of aluminium is cast around the particles to form a solid composite block. The resultant composite is aluminium wettable. Superstrength metal composite material and process for making the same Louat, N.P., Provenzano, V., Imam, M.A. and Sadananda, K. (Secretary State of the Navy, Washington, DC, USA) US Pat 5 333 667 (2 August 1994) Particles with an average size of less than 1 }am are placed inside a hollow cylinder composed of a metallic matrix material. The particles have a lower ductility than the cylinder but a higher melting point. The cylinder is capped with the matrix material and the whole is wrapped in a foil which has higher melting point than either the particles or the matrix. The foil wrapped cylinder is placed in a jacket which is then evacuated and hot pressed isostatically at a temperature between the melting points of the matrix and the particles to produce a metal matrix composite composed of the particles embedded in the matrix material. Process for coating carbon fibres with pitch and composites made therefrom Edie, D.D. and Klett, J.W. (Clemson University, Clemson, SC, USA) US Pat 5 334 414 (2 August 1994) Carbon fibres are passed through a pressurized air comb spreader to form a spread tow on which pitch is deposited such that it coats the individual filaments. The coated tow is formed into a carbon/carbon composite by carbonization.