GB1484283A - Heat treating polyurethane-sized glass fibres - Google Patents

Abstract

1484283 Treating glass fibres BAYER AG 19 Nov 1974 [20 Nov 1973] 50025/74 Heading D1P A process for the manufacture of a glass fibre reinforced plastics material comprises finishing glass fibres with polyurethane sizes or with sizing systems containing polyurethanes, subsequently heating the fibres and implanting the fibres into synthetic plastics material. The polyurethane may be applied as an aqueous dispersion or as a solution, for example in water, toluene or acetone. In addition to the polyurethane, lubricants such as alkoxylated fatty acid amides and adhesion promoters such as aminosilanes and emuisifiers may be present. The polyurethane size may be applied to the fibre in an amount to 0.3 to 3% and the heat-treatment may be carried out discontinuously or continuously. In the discontinuous process a plurality of sized elementary filaments grouped together in tows may be wound to produce rovings. The bobbins of rovings with or without a sleeve are passed into a heat-treating oven at the desired temperature, for example 550‹C for 10-30 mins. In the continuous process the heat treatment may be carried out by drawing the filaments over a metal plate which is at an elevated temperature or over a heating loop which may be heated electrically. The reinforced plastics material may be manufactured by impregnating bundles of glass fibres with liquid reactive resin compositions which may contain solvents. Suitable resins are unsaturated polyester resins, epoxy resins, phenol-formaldehyde resins, urea-formaldehyde resins, melamine-formaldehyde resins, furane-formaldehyde resins, cyanate resins, polyamides, polyurethane resins, hydrocarbon resins and silicone resins. Also the glass fibres may be introduced into thermoplastics materials in kneaders or screw mixers. Suitable thermoplastics are polyolefins, styrene polymers and copolymers, halogen-containing olefin homopolymers and copolymers, polyvinyl acetate, polyacrylic and polymethacrylic compounds, heteropolymers such as polyoxymethvlene and polyphenylene oxides, cellulose derivatives, polycarbonates polyesters and polyimides.