reinforcement of thermoplastic matrices Gaillard, P. and Robinet, J.-C. (Norsoior, Cedex, France) US Pat 4 897 449 (30 January
/99O) The interpolymer comprises at least one elastomeric inner phase with T8 ~< 25°C and a relatively hard non-elastomeric outer phase with Tg > 25°C. The inner phase is polymerized from 50-99.9 weight % of at least one alkyl or aryl acrylate monomer, 0-49.9 weight % of at least one other monoethylenically unsaturated monomer that is copolymerizable with the first monomer, 0.05-8 weight % of at least one cross-linking polymer and 0.05--6 weight % of at least one grafting monomer. The outer phase is polymerized in the presence of the inner phase from 50-99.9 weight % of at least one Ct-C4 alkyl methacrylates, 0.1-50 weight % of at least one monoethylenically unsaturated monomer copolymerizable with the first monomer and 0-5 weight % of at least one chain limiting agent. The resulting product has a bimodal particle distribution, the ratio of which varies between 10:90 to 90:10, of particles whose mean diameter is between 40 and 150nm and particles whose mean diameter is between 160 and 340 nm.
PROCESSES Process for the production of a composite tool Nakai, T., Hara, A. and Yazu, S. (Sumitomo Electric Industries, Ltd, Osaka, Japan) US Pat 4 890 782 (2 January 1990) An insert consisting of (1) a sintered alloy containing as predominant component at least one of WC, (Mo,W)C, TiC, TiN and Cr3Cz, (2) a composite compact containing at least 50 volume % diamond powder with a hard sintered alloy substrate, and (3) a composite compact containing at least 20 volume % BN powder with a hard sintered alloy substrate, is bonded to one of Ni, Co or alloys thereof. One of the inserts and a support consisting of steel or a hard sintered alloy is rotated at high speed and the hard sintered alloy bonded to the insert is subjected to frictional heating so that it flows and bonds the insert to the support. Method of consolidating composite articles Peacock, D.G. and Kirkham, S.W. (Textiiver SA, Crepy-en-Valois, France) US Pat 4 891 179 (2January 1990) A tubular composite article comprising a polymeric matrix and a fibrous reinforcing material is progressively wrapped in at least one sheet as it enters a consolidation zone where it is progressively subjected to the consolidation temperature and pressure. The sheet acts to maintain the composite article substantially free of longitudinal forces. Method for producing composi~ ceramic structures using dross Nadkarni, S.K. and Raghavan, N.S. (Lanxide Technology Company, LP, Newark, DE, USA) US Pat 4 891 345 (2 January 1990) A permeable filler material containing at least one comminuted dross material obtained from a metal melting operation is placed next to a parent metal. The whole is heated to a temperature above the melting point of the metal but below the melting point of the oxidation reaction product formed
between the molten metal and an oxidant present in the system. The molten metal is drawn through previously formed oxidation reaction product and the filler material so that the filler is infiltrated with the resulting oxidation reaction product. The dross has an affinity for the oxidation reaction product and therefore enhances its formation. Production process of polyolef'm resin composition containing inorganic filler Abe, M., Kawai, Y., Hoshino, M. and Sekiguchi, K. (Mitsui Toatsu Chemicals, Incorporated, Tokyo, Japan) US Pat 4 891 392 (2 January 1990) The inorganic filler is pulverized with 0.01-15 parts by weight per 100 parts of filler by a surface treatment agent using a jet-stream means in the dry or semi-dry state. Between 3 and 9 parts by weight of the treated filler are mixed with 1 part of polyolefin resin and the resultant mixture is granulated. Between 1 and 80 weight % of the granulated mixture is mixed with pellets or granules of an unfilled polyolefin resin to produce a mouldable polyolefin resin containing an inorganic filler. Method for making a reinforced article for an internal combustion engine Ban, K. and Daimaru, A. (Honda Giken Kogyo Kabushiki Kaisha, Tokyo, Japan) US Pat 4 892 130 (9 January 1990) A bundle of unidirectional inorganic reinforcing fibres including a proportion of metallic fibres is placed in a heat-resistant shaping container and is heated so that the metallic fibres are partially fused to each other. The partially fused bundle is positioned in a mould leaving a fixed minimum gap surrounding the bundle and a molten light metal alloy is squeeze cast into the mould to form a metal-matrix composite component. Method of making filament growth composite Perrotta, A.J., Grubbs, D.K., Quayle, W.H. and Gurganus, T.B. (Aluminium Company of America, Pittsburgh, PA, USA) US Pat 4 892 693 (9 January 1990) A process for forming a novel composite consists of forming a solid matrix encompassing crystalline filaments which have been grown substantially unidirectionally on (but not perpendicular to) a substrate. Fibre/resin composites, and method of making the same Drain, K.F., Nativi, L.A. and Thompson, R.T. (Loctite Corporation, CT, USA) US Pat 4 892 764 (9 January 1990) A fibre/resin composition is described wherein the resin is comprised of two parts, one of which is curable with actinic radiation whereas the other is not. The first resin is cured and holds the structure in place prior to the curing of the second resin. Composite material and process for producing the same Okada, A., Kawasumi, M., Kohzaki, M., Fujimoto, M., Kojima, Y., Kurauchi, T. and Kamigaito, O. (Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi, Japan) US Pat 4 894 411 (16 January 1990) A process for forming a composite material is described in which a layered clay mineral with a cation exchange capability of 50-200 milliequivalents per 100 g is brought into contact with a swelling agent, thus forming a complex
which can be swollen with a polyamide monomer subsequently mixed into the complex. The monomer is polymerized by heating the mixture and the crystalline or molecular structure of the polyamidecontaining resin is controlled by adding, either at this stage or during the mixing, either (1) at least one polyamine selected from diamines, triamines, tetramines, pentamines and aliphatic polyamines or (2) 0.05-5 parts by weight to 100 parts by weight of resin of at least one stabilizer selected from phenol derivatives and organophosphoric compounds. Stabilisation of extremely lightweight aggregate concrete Hedberg, B. and Berntsson, L. (G~teborg, Sweden) US Pat 4 895 598 (23 January 1990) A method is given of producing concrete with a fully dry density between 700 and 1200 kg m -3 from hydraulic cement, sand, fine and extremely lightweight particles, air bubbles and water mixed with coarse lightweight aggregate. The low density of the mortar results from: (1) replacing sand at least partly by an equivalent volume of 20-500 ~tm diameter air bubbles, resulting in 5-30 volume % of the mortar being air bubbles; (2) 5-20 volume % being expanded organic and inorganic aggregates 0.2-2 mm in diameter with a particle density less than 200 kg m 3; and (3) 0.1-5.0 % of the cement weight being polymer and equivalent organic microparticles. The microparticles consist of at least two different types present in weight ratios between 1:3 and 1:6 respectively: 0.11.0 ~tm diameter synthetic polymer particles with 0.1-5.0 weight % anionic or a combination of anionic-nonionic calcium stable surfactants absorbed on the surface, and 0.510 ~tm diameter natural or synthetic polymer particles with 0.1-5.0 weight % anionic or a combination of anionic-nonionic calcium destabilizable surfactants absorbed on the surface. Method for welding and laminating polyamides Avramova, N.V., Fakirov, S.C. and Schultz, J.M. (University of Delaware, Newark, DE, USA) US Pat 4 895 612 (23 January 1990) Separate polyamide bodies are wetted with a solution of paraformaldehyde in paraformaldehyde-methanol containing traces of an alkali metal hydroxide and a catalytic amount of anhydrous oxalic acid. The wetted bodies are subsequently pressed at a pressure from 0.05-5 MPa and a temperature from 5--40°C for a sufficient time to allow the creation of methylene bridges between nitrogen atoms of the separate methylene bodies. Crosslinked composite membrane and process for producing the same Honda, Z., Komada, H. and Karakane, H. (Agency of Industrial Science and Technology, Tokyo, Japan) US Pat 4 895 685 (23 January 1990) A cross-linking solution containing a watersoluble polysaccharide with a sulphonate and/or a sulphonate acid group and a polyfunctional melamine compound is applied to a porous base. The solution is dried and cross-linked simultaneously to give a crosslinked skin layer with covalent bonds on the porous base and the process is repeated.
COMPOSITES. SEPTEMBER. 1991