GB1133894A - An apparatus and a process for extruding a mortar containing a thermo-setting synthetic resin and a mineral filler - Google Patents

Abstract

1,133,894. Screw-extrusion machines; laminates. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 17 Jan., 1967 [19 Jan., 1966], No. 2451/67. Headings B5A and B5N. [Also in Division E1] A mortar comprising a thermosetting synthetic resin and a mineral filler is extruded in rod or sheet form using a screw extruder whose screw has a compression ratio within the range 1 : 1À1 and 1 : 1À5 and wherein the crosssectional area of the die orifice is between 8 and 20% of the minimum cross-sectional area of the axial flow path between screw 11 and barrel 10. Compression ratio is defined as the ratio between the maximum and minimum volumes contained between adjacent turns of the screw flight and differs from unity by, e.g. having a core of increasing diameter, a barrel of decreasing diameter or a flight of decreasing pitch, the changes occurring in the downstream direction. As shown, the extrudate is deposited as adjacent strips on a substrate (not shown) by movement of the extruder, the strips adhering to the substrate and being acted upon by a roller 18 to smooth them into a uniform sheet. Alternatively rods may be extruded on to a substrate using an in-line die with again a mortar sheet being formed by rolling. Substrates specifically mentioned are the walls of tunnels or swimming pools or the surfaces of roads which may be completely coated in the manner above described. It is also mentioned that the extrudate in sheet form may be cut to form tiles. In a specific mortar composition an epoxy resin is mixed with fine-grained sand and quartz powder and an accelerator and polyamine resins as hardeners are also included. Such compositions may also contain colorants.