Abstract:

In order to investigate the effects of the novel dynamic three-screw extrusion moulding technology on the mechanical properties of the specimen , PP/CaCO₃ composites were selected as the object to reveal the vibration parameters on the mechanical property and the section morphology structure. In the investigation , the vibration force with a frequency varying from 0 to 60 Hz and an amplitude varying from 0 to 250μm was loaded on a three-screw extruder , and the tensile strength and the impact strength of the specimens were tested , followed by a SEM measurement. The results show that there exists an optimum point for the response of mechanical properties to vibration parameters , and that , as compared with the extrusion in the steady state , the composites sho节an increase in impact strength by 2 1. 7 % at a 20 Hz and 225μm vibration , and an increase in tensile strength by 10. 4% at a 20 Hz and 145μm vibration.

Key words: polypropylene, calcium carbonate, composite, mechanical property, vibration frequency, amplitude