| 摘要 |
The process and the device in question differ from the known ones in that they permit the working of the PVC in powder form at very low temperatures, while achieving a high degree of plasticity even with a limited percentage of stabilisers and slip agents. Thin films having a thickness of 10 mu to 60 mu are obtained by continuously introducing the raw material in the form of powder, after intense mixing with stabilisers and slip agents, into the feed aperture of a single-screw extruder. Said single-screw extruder exhibits 7 different zones: an inlet zone (E) preferably without heating; a compression zone (K1) with slight heating; a heated homogenisation zone (H), a heated decompression zone (D); a heated degassing zone (G); a heated compression zone (K2) and a heated expulsion zone (A). <IMAGE> |
