Properties of elongational flow injection-molded polyethylene. Part 1: Influence of mold geometry

Injection molding of polyethylene was carried out using molds that introduce axial elongational flow during the filling process, As compared with conventional injection-molding methods, the present technique yields polyethylene materials having higher mechanical strengths (σ ≈ 150 MPa). The σ-value of the moldings can be systematically monitored by adequately varying the elongational flow through modification of the mold geometry. Geometrical features of the volume containing the melt before injection as well as geometry of the die, the extruder, and the inlet influence the overall elongational flow, and thus, the mechanical strength of the moldings.