Abstracts of patents Compiled by Dr J. W. Youren, IMRU, Industrial Innovation, Queen Mary College (University of London)
US PA TENTS Fibre board product from wood particles having a 5-25% moisture content prior to steaming and mechanical reduction in the formation process Brooks, S. H. W. and Raddin, H. A. (Miller Hofft lnc) US Pat 3 668 286 (6 Jun 1972) Wood particles with a moisture content of 5-25% are subejcted to steaming and mechanical reduction which is followed by mixing with unreacted thermosetting resin having a solids of 45% and a viscosity of less than I00 cP. This composite is compressed to a required thickness between RF heated platens to at least partially react the components. Process for producing whisker-reinforced metal matrix composites by liquid-phase consolidation Divecha, A. P. and Lare, P. J. (American Standard Inc) US Pat 3 668 748 (13 Jun 1972) Metal matrix and fibres are consolidated under pressure, the temperature being sufficient so that the former is partly in a liquid and a solid phase. Approximately ¼ of the matrix is in the liquid phase and contains up to 50% by volume of oriented whiskers. The composite is then extruded into a die cavity to arrive at the consolidated final shape, heating being continued until the cavity filling is complete. Continuous carbon fibre tapes Phillips, L. N. (Minister of Technology, UK) US Pat 3 669 158 (13 Jun 1972) Tapes consist of high strength high modulus carbon fibres and optionally glass fibres suitable as a pre-impregnated tape in a mechanical winding process, where light cross weave glass fibre ( 1 - 1 0 filaments) at a frequency of 2 - 1 0 threads per inch are used. Stress-oriented filament winding in composite panels Sinizcr, D. I. and Toy, A. (North American Rockwell Corp) US Pat 3 669 364 (13 Jun 1972) Removable terraced peripheral edges on a rotating mandrel are adapted to receive successive windings of thin filaments in several separate layers to form reinforced composite panels. Mandrel edges are reversed in position between each winding step to allow filament winding at stressoriented cross-ply angles with a minimized filament wastage, after which components are diffusion bonded. Impregnating and lamination resin solutions methods and articles produced thereby Raymond, D. G, (SCM Corp) USPat 3 6 6 9 727 (13Jun 1972) New melamine acrylate-polyester resin solutions and impregnation methods for
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paper, wood cloth, fabric, asbestos and other webbed fibrous or porous materials are described. Carbon fibre reinforced polyurethane composites Haggis, G. A. and Jones, M. E. B. (ICI Ltd) US Pat 3 669 920 (13 Jun 1972) Carbonized fibres (20-75 wt%) are dispersed in an isocyanate terminated prepolymer prepared by reacting a polyisocyanate with a polyol and at least one of which contains a cyclic group in a chain between two functional groups and has a heat distortion temperature of more than 50°C. Applications include aerofoil blades. Composites and intermediates therefore Prescott, R. (Great Lakes Carbon Corp) US Pat 3 671 285 (20 Jun 1972) Composite pre-impregnated tapes and sized carbon fibres are prepared by coating carbon fibre with a high crosssection metal or metalloid and resin and then curing while irradiating the fibre with a source of thermal neutrons to improve the resin carbon-fibre bond.
Glass fibre reinforced composites and method of making the same Longrneadow, M. B. and Campbell, J. O. (Monsanto Co) US Pat 3 671 378 (20 Jun •972) Thermoplastic resin is blended with glass fibre concentrate capsules containing 10-80 wt% of glass strands of length 1 / 3 - 3 / 4 in arranged in collimated array and then encapsulated with resin. See also US Pat 3 671 384. Fibrous carbonaceous composites and method for manufacturing the same Trent, P. E. and Miner J. E. (USAEC) USPat 3 671 385 (20Jun 1972) A slurry of discrete carbon fibres, carbonizable particulate resin and water soluble starch is sprayed onto a mandrel coupled to a vacuum system to remove excess water. This is heated to carbonize the starch and resin which bind the fibres Treatment of carbon or graphite fibres and yarns used in fibre reinforced composites Ray, J. D. and Steingiser, S. (USA Sec Airforce) US Pat 3 671 411 (20 Jun 1972) A fibre or yarn used as an anode in an aqueous caustic solution as electrolyte is treated electrolytically to improve the surface characteristics which results in improved bonding in composite matrices leading to doubled shear strength values. Glass reinforced polyester resins containing PTFE and flame retardant additives Abolins, V. (General Electric Co) US Pat 3 671 487 (20Jun 1972) Flame retardant composites are prepared
from flammable linear polyesters, glass, flame retarders and PTFE, the latter controlling dripping. The flame retarder level is sufficient to prevent burning but without reducing the physical properties of the composite.
Reinforced carbon and graphite articles Ehrenreich, L. C. (Carborundum Co) US Pat 3 672 936 (27 Jun 1972) Reinforced carbon articles consist of carbon fibre shapes bonded by a carbon binder and the in situ reaction product of carbon and a boron containing additive selected from boron, boron nitride, silicide and refractory borides. Method of manufacture of carbon fibre~ Whitney, I. (Rolls Royce Ltd) USPat 3 673 035 (27Jun 1972) Sheet or tape from carbon fibre is produced in which a plurality of sheets or tapes of polyacrylonitrile, consisting ol l0 s fibres, is fed through furnaces in which constituents other than carbon are driven off. Glass fibre reinforced elastomers Marzocchi, A. (Owens-Coming Fiberglas Corp) US Pat 3 673 150 (27Jun 1972) Glass fibre-elastomer bonding is improved when individual glass fibres or bundles are impregnated with a polysulphide composition. Glass fibres sized with a composition comprising a vinylic aromatic diolefin eopolymer and a hydrolysable silane Vanderbilt, B. M. and Fasnacht, J. J. (Esso Research and Engineering Co) US Pat 3 674 542 (4 Jul 1972) Glass fibres are coated with a carrier medium having 1-10% solid non-blocking unsaturated copolymer of a vinyl aromati,: and a C 4 - C s diolefm in which more than 50% of the unsaturation is in the 1, 2 or 3, 4 type, the average molecular weight being 1 0 0 0 - 3 0 000, the carrier also containing 0.2-2.0% hydrolysable silanc.
Production of fibre reinforced composites Kalmin, I. L. and Breckenbridge, G. J. (Celanese Corp) US Pat 3 674 581 (4 Jul 1972) Carbon fibres are compacted with a flowable matrix in a heat-shrinkable mould and solidified to a mouldable B-stage or rigid C-stage consistency. These highly oriented reinforced composites are useful as high performance structural elements. Carbon fibre filled composite materials Giltrow, J. P. and Kinner, G. It. (NRDC) US Pat 3 674 689 (4 Jul 1972) Bearing surface components consist of metal-coated carbon fibres in a matrix of synthetic resin. They have low we,rates and a low friction.
Carbon materials and articles Bickerdike, R. L. and Hughes, G. (NRDC) US Pat 3 676 160 (11 Jul 1972) A low conductivity high shock resistant mould is made from fibrous carbon bonded in non-fibrous carbon. This may be repeatedly used to cast grey iron.
COMPOSITES . JANUARY
1973