Smart Processing of Plastics Through Vibration Controlled Shear-Thinning and Orientation

Abstract

This paper covers the technology of melt vibration during the molding of plastic material (more specifically at low frequency) to reduce the viscosity and ease processability and to produce orientation benefits. The effect of vibration frequency and amplitude on melt viscosity is explained in terms of shear-thinning criteria. The effect of pressure, temperature and cooling rate on shear-thinning is also reviewed to predict how these variables interfere with melt vibration. Applications to injection molding, extrusion and blow molding of uneasily processable plastic melts (such as metallocenes polyolefins) are suggested.