Push–pull-processing (PPP) is a particular method of injection moulding with enlarged capabilities to control the melt flow during solidification. While the melt is solidifying from the mould wall to ...the mould centre an oscillating motion through the cavity maintains the melt flow. Aims were to investigate the capabilities of the process to control orientation of fibres and matrix and its effect on fibre length since this determines significantly the mechanical properties of plastic parts. Processing parameter variations were carried out on a Ferromatik K110/S60-2K injection-moulding machine. Sample plates were produced of short and long fibre reinforced polypropylene. The process and the control of it are described in the paper. Fibre orientation and fibre length were measured. Inter-laminar shear strength (ILSS) tests were performed to investigate the strength between shear layers. WAXD was applied to investigate orientation in the matrix. The results were correlated to process settings.
