| 摘要 |
1,249,217. Moulding polyamide. BADISCHE ANILIN- & SODA-FABRIK A.G. 28 Feb., 1969 [2 March, 1968], No. 10826/69. Heading B5A. A process for the production of bubble-free mouldings by activated anionic polymerization of lactams in which a melt containing a catalyst in reservoir 1 and a melt containing an activator in reservoir 2 are heated separately to polymerize in a mould, is characterized in that the melt containing a catalyst and the melt containing an activator are supplied simultaneously to a mixing zone 12 from which the united melt is forced upwardly into the mould 15. Valves 13 and 14 control the supply of the melts into the mixing zone 12 the valves being connected to circuits 3, 3a, 4, 4a supplied from the reservoirs 1 and 2 respectively and including valves 7 and 8, 9 and 10, and pumps 5 and 6 respectively. Lactams having six to twelve ring carbon atoms are said to be suitable. Alkali metal lactams are suitable catalysts and suitable activators are N-acyllactams, isocyanates, N- cyanolactams, substituted ureas, reaction products of carbamyl chlorides with heterocycles such as imidazole. Additives, e.g. reinforcements such as glass fibre; fillers such as metal powder, slate flour, diatomaceous earth; lubricants; delustrants; and stabilizers may be used. The mixing chamber and mould may contain an inert gas such as nitrogen. The weights of the constituents, the flow rates, filling times and mould dimensions are given. |
