超高分子量聚乙烯单螺杆挤出的输送机理研究

RESEARCH ON CONVEYING MECHANISM OF ULTRA HIGH MOLECULAR WEIGHT POLYETHYLENE SINGLE-SCREW EXTRUSION

以超高分子量聚乙烯 (UHMW- PE)专用单螺杆挤出机 ,研究和分析了 UHMW- PE在单螺杆挤出过程中的熔融输送机理。结果表明 ,UHMW-

Ultra High Molecular Weight Polyethylene(UHMW PE) which has excellent performances, is very difficult to be processed. By means of Φ45 type of experimental single screw extruder and Φ65 type of industrial pipe line, the successful extrusion of UHMW PE has been realized and the mechanism of melt conveying was studied. In the feeding zone, the powdery material moves as solid plug, in the compression zone, the melt and non melt moves as a integer, in the metering zone, the melt moves as a spiral strip. The results show that, motion of UHMW PE in the screw is a process varing from powdery solid to semi solid to high visco elastic solid, so the conveying mechanism is typical plug flow. This conclusion is helpful to design reasonable UHMW PE single screw extruder.