Abstracts of patents UK PA TENTS
Production of impregnated rovings (Imperial Chemical Industries Limited) UKPat I 334 702 (24 Oct 1973) The rovings are separated into several bundles containing one or more filamerrts, using a comb or a series of ribbed bars, before being passed through a bath of powdered resin which is subsequently fused. Method of producing an article impregnated with thermosetting resin (Shell Internationale Research Maatschappij) UK Pat I 335 098 (24 Oct 1973) A flexible open cell polyurethane foam is impregnated with an epoxy resin, a layer of fibrous material such as glass placed on each side and put into a mould. The remaining space in the mould is charged with a polyurethane foaming composition. The pressure of the foaming operation forces resin out of the foam to impregnate the ,glass fabric, the resin cures and the product is a foam with a rigid skin. Method of treating carbon fibres (Great Lakes Carbon Corporation)
UK Pat 1 335 484 (31 Oct 1973) Shear strength Of composites containing 45 to 65% fibre is increased if the fibre is first treated with an aqueous solution containing 15 to 45% sulphuric acid and 5 to 20% sodium dichromate, preferably at reflux temperature, for 10 to 60 minutes.
polymer/hardener mix onto a nonadherent support followed by a layer of natural or synthetic fibres. This is repeated twice to give a six-layer composite which is then allowed to cure.
Plastics fdm laminate (The Dow Chemical Company) UKPat 1 335 610 (31 Oct 1973) A film with increased low temperature flexibility is produced by laminating a sheet of normally crystalline vinylidene chloride-vinyl chloride copolymer containing 2 to 6% of an ethylene-vinyl alcanoate such as ethylene-vinyl acetate with a sheet of an ethylene-unsaturated ester copolymer which may also be ethylene-vinyl acetate.
Improvements in plastics material reinforced with carbon and other fibres (TAC Construction MBterials Ltd) UK Pat 1 336 128 (7Nov 1973) The replacement of 5 to 33.3 % of the fibrous reinforcement in a thermoplastic or thermosetting resin composition by carbon fibre produces a disproportionate increase in wear resistance. Strength is also increased substantially.
Producing novel silicon dioxide fibres
aluminium or aluminium alloy
(Bayer Aktiengesellschaft) UK Pat
1 335 754 (31 Oct 1973) A method of making high strength quartz fibres involves spinning a solution of a tetra-alkoxysilane which has been hydrolysed with at least 2 mols of water per mol of silane or a solution of an alkoxy-polysiloxane which has been hydrolysed with water so that at least 0.5 mols of water per alkoxy grOuP are present. Spinning in either case should be in the presence of 0.001 to 5% of a poly-lower-alkylene oxide, preferably polyethylene oxide with a degree of polymerisation over 5 000.
Method of manufacturing a strengthened hollow synthetic resin article (Miharu Yamashita) UK Pat 1 335 500 (31 Oct 1973) Rotational moulding of glass reinforced polyesters containing 10 to 30% glass fibres is made possible by first coating the fibres with an unsaturated polyester resin or emulsion. On mixing with more resin little or no viscosity increase results and the mix will flow in the mould.
Improvements in or relating to the production of carbon fibre (National Research Development Corporation) UK Pat I 336 123 (7Nov 1973) A continuous process for making carbon fibre involves feeding a synthetic fibre into an oxidising atmosphere at 200 ° to 270°C under continuous tension by having the speed of movement at the exit greater than at the entrance. This allows low thickness filaments to be made from commercially available fibres of greater thickness.
Process for the manufacture of composite materials (Pechiney Ugine Kuhimann) UK Pat I 335 563 (31 Oct 1973) A leather-like material is made by spraying an isocyanate-terminated pre-
Method of impregnating a layer of fibres with a matrix material (The Secretary of State for Defence) UK Pat I 336 127 (7 Nov 1973) A method of impregnating a fibre sheet with resin which is particularly
useful if the sheet has no cohesive strength or when the resin and hardner are not soluble in a single solvent involves spreading the resin-hardener mix on a release paper, placing the fibres on the surface and spraying with a solvent for the resin.
Titanium or titanium alloy clad composite (Pfizer Inc.) UK Pat I 336 204 f7Nov 1973) An economical composite having the surface properties of titanium is made by cleaning and removing oxide from sheets of aluminium and titanium, heating to, preferably, 316 ° to 454°C (600 ° to 850°F), contacting the surfaces under rolling pressure to effect a thickness reduction of 3 to 50 % and post-heating at 426 ° to 538°C (800 ° to 1 000°F). Process for preparing epoxy resin laminates and resulting products (Shell Internationale Research Maatschappij) UK Pat I 336 462 (7Nov 1973) A process which allows greater flexibility to the laminator regarding the resin composition used involves impregnating a reinforcing material with a mix. ture of a liquid glycidyl polyether of 2,2-bis (4-hydroxyphenyl) propane, 0.05 to 0.25 % of a tertiary phosphine, a dihydric phenol such as bisphenol A, a solvent and an amine curing agent.
Thermoformable laminated sheet material (Uniroyal Inc.) UK Pat I 336 764 (7Nov 1973) A thermoformable material with good low temperature impact properties is made by laminating sheets of ABS copolymer on each side of a sheet of an elastomeric block copolymer such as is formed from styrene and butadiene.
C O M P O S I T E S . S E P T E M B E R 1974