Improvement of the flow of polyethylene terephtalate (PET) by interposition of ball strata at the inlet of the spinning die

Abstract

Abstract Polyethylene terephthalate (PET) is a material developed by industrial manufacturers, but which is also abundantly found as a recovery material in many daily activities. Since it is largely used in the textile industry, the objective of this work is to improve the flow of polyethylene terephthalate (PET) in textile spinning as an application using certain polymers to produce quality fabrics. The methodology adopted here is to interpose layers of balls to form a porous medium at the entry of a melt-index in laboratory or in industrial setting. This allowed to characterize the materials’ flow properties such as flow rate, flow index and viscosity. This study used two grids of diameter 9.50 mm to form a layer of ceramic beads of equivalent diameter included in the intervals of [0.25 - 1.6 mm] and [1.6 - 2.5 mm]. Under an equivalent load of 2,6 kg, applied to the material for the measurement of both its fluidity index, the density and its viscosity. The results obtained show a decrease in the fluidity index compared with the manufacturers’ reference values when the ball states are interposed at the input of the die. This was justified by a braking of the flow of the material into the porous medium formed by the balls which constitute the interposed porous state. Moreover, the increase in the viscosity of the molten polymer after interposing states confirmed the opposite behaviour of these two characteristics. Future works seek to show the influence of ball size on the flow characteristics such as viscosity, fluidity index and hot density of the material.