| 摘要 |
1,135,551. Mixing plastics materials. H. GRIGULL. 4 Jan., 1966 [7 Jan., 1965], No. 386/66. Heading B1C. Thermoplastics material, e.g. P.V.C., is fed via hoppers 11, 12, through zones 1 . . . 4, e.g. containing an extrusion screw, to an outlet 6, the hoppers and zones being evacuated to a pressure preferably below 10 torrs. The temperatures in the zones rises from that in zone 1, which is at least 10% above the maximum usable under atmospheric pressure without thermal decomposition occurring, to a maximum in zone 3. In zone 4 the material is cooled to about 80% of the said maximum usable under atmospheric pressure. |
