Siliceous materials (ICI) Br Pat 1 514 922 (21 June 1978) Polybutadiene with terminal hydroxyl groups is reacted with precipitated silica, to form bound polymer. The product is a useful filler for rubbers and can be polymerised into it during vulcanisation,
Titanium compounds (Tioxide Group Ltd) Br Pat 1 515 645 (28 June 1978) Stearate esters of titanic acid reduce viscosity of filler dispersions ( T i 0 2 and CaC03) in plasticisers and polymer melts. The coating of CaC03 filler with these titanates improves the impact resistance of filled polypropylene.
Process for producing carbon fibres (Toho Beslon Co Ltd) Br Pat 1 515 246 (21 June 1978) A process is described for making good quality fibres continuously from a polyacrylonitrile based precursor. This is done by careful control of the shrinkage to between 40-70% during oxidation, Transparent beta quartz glass-ceramics (Corning Glass Works) Br Pat 1 515 827 (28 June 1978)
Improvements in curable epoxide compositions (General Electric Company) Br Pat 1 516 351 (5 July 1978) Epoxy resins containing a radiation sensitive aromatic halonium salt eg diphenyliodonium tetra-fluoroborate which generates a Lewis acid on radiati.on with light of wave length 1849°A - 4000°A, can be stored without fear of gelation. No gases are evolved and imperfection free laminates are possible.
The/3-quartz phase crystallises out of a Li20/Mg0/Zn0/AI203/Si02/Zr02 glass in a fine grained form at 850-950°C. The advantage over previous examples is its transparency, Apparatus for adsorbing harmful substance and method for adsorbing harmful substance thereby (Toyobo Co Ltd) Br Pat 1 515 874
Plastisal of an organic polymer and a plasticiser (Teroson GmbH) Br Pat i 516 510 (5 July 1978) A copolymer of t-butylacrylate and an aliphatic methacrylate can be dispersed in a plasticiser to form a plastisol. These compositions have superior properties to their conventional pvc counterparts,
(28 June 1978) Active carbon fibre fabrics are described for the above use. Activation of carbon fibres from
Improvements in curable epoxide compositions (General Electric Company) Br Pat 1 516 511 (5 July 1978) Aromatic onium salts of 0, S, Se, Te will also generate Lewis acids, on irradiation, capable of curing epoxy resin compositions (of Br Pat 1 516 351 and 1 516 352).
various precursors is achieved by heating with steam at about 1000°C.
Inhibitors for alkali-glass reactions in glass-fiber reinforced cement products (W.R. Bonsai Company) Br Pat 1 516 053 (28 June 1978) Glass fibre-reinforced cement containing an alkali reactive ingredient such as a finely divided Si02 is described. The alkali scavenger is in stoichiometric proportion so that the glass fibres are protected,
Process for producing carbon fibres (Japan Exlan Co Ltd) Br Pat I 516 247 (28 June 1978) The precursor is a copolymer of acrylonitrile impregnated with an amino-siloxane. The problems of filament breakage and fluffiness are removed by this process. The crosslinking cyclisation may be promoted by the amine group.
Method of manufacturing shaped articles from crystalline acrylonitrile polymers and copolymers (Ceskoslovenska Akademie Ved) Br Pat 1 517 083 (12 July 1978) Crystalline or quasi crystalline acrylonitrile polymers and copolymers can be shaped into articles by cooling down a polymer solution to produce a thermoreversible gel whose shape is maintained by removal of the solvent by washing with a non-solvent for the polymer, A method of making a radome by moulding (Eltro GmbH Gesellschaft fur Stahlungstechnick) Br Pat 1 517 617 (12 July 1978)
The female half of the mould contains a stocking and a tablet of fibre-reinforced epoxy resins. With the mould closed the resin melts and spreads out with the fibres over the stocking thereby producing an article of the correct shape and finish.
Method of fabrication of parts of three dimensional fabrics (Commissariat A l'Energie Atomique) Br Pat 1 517 671 (12 July 1978) Layers of two directional carbon-fibre fabrics (or alternating the layers in two directions) are placed on a pyrolysable support and stitched to it. The whole is heated in a gaseous hydrocarbon atmosphere at 800-1200°C to deposit pyrolotic carbon onto the threads. Method for moulding resin bonded high friction materials (Pennwalt Corporation) Br Pat 1 517 851 (12 July 1978) Asbestos fibre bound with a suitable thermosetting resin, for use in brake shoes etc has serious processing problems such as accurate metering into the compression mould. An enclosed mixing, conveying and screw plasticising machine, for making preforms suitable for compression moulding, is described. Low cost method of fabricating carbon composites (Ducommun Inc) Br Pat i 517 947 (19 July 1978) A slurry method is used to make an article from short randomly oriented thermoplastic fibres (mainly from pan). Compressing and fusing at 150 - 210°C produces an interlocked structure, which can be oxidatively carbonised; carbon is the n deposited in the interstitials at 1000- 1300°C from a hydrocarbon atmosphere. Improvements relating to glass fibre reinforced cement materials (Pilkington Brother Ltd) Br Pat 1 518 144 (19 July 1978) A high shear mixing process in the presence of a deflocculating agent is used to break down cement agglomerates before the addition of short glass fibres in a low shear process. The slurry formed has improved flow characteristics. The damage to the 25 mm glass strands is minimised so that improved strengths result.
COMPOSITES . JANUARY