| 摘要 |
1352391 Fibre-reinforced filaments IMPERIAL CHEMICAL INDUSTRIES Ltd 19 May 1972 [10 June 1971] 19889/71 Heading B5B A fibre reinforced thermoplastic material is made by extruding from a melt 1 a plurality of filaments, passing the filaments into a bed of powdered thermoplastic material 6 of lower melting point than the filaments, causing the filaments to converge while they are in the bed so that they form a bundle 7 which is impregnated with the thermoplastic powder, and heating the impregnated bundle, as by passage through tube 8 surrounded by heating jacket 9, to a temperature above the melting point of the thermoplastic powder but below the melting point of the filaments. Desirably, the filaments begin to converge immediately on leaving the spinneret and pass into the bed before convergence is complete, the filaments entering the bed while they are still hot. In the apparatus of Fig. 2 the extruded filaments are drawn together by passage around the annular groove of pulley wheel 11 which is rotatably suspended within a fluidized bed of thermoplastic material. The bed may be fluidized by means of a non- reactive gas and the filaments extruded directly thereinto so that they enter the bed before they contact the air. After passage through die 10, the bundle is consolidated into a lace. The product so made may be chopped into granules for use in injection moulding processes; or fed to a heated profiled die to produce a fibre reinforced thermoplastic section or sheet or wound on to a mandrel to form sections or removed from the mandrel as a web for pressing into sheet. Alternatively the lace may be allowed to fall on to a moving belt, the lace being traversed and coiled on the belt to form a covering which may be pressed or rolled into sheet, or short lengths of the lace may be so treated. The filaments may be glass or metal. A wide variety of thermoplastic materials may be used, including cellulose esters, polyamides, polyesters, polyethers, polyolefins, polystyrene, polyvinyl esters, polyvinyl butyral, and polyacrylonitrile. |
