Mathematical modeling of poly(ethylene terephthalate) air drawing in spunbonding nonwoven process

Abstract

The air drawing model of PET polymer in a spunbonding process has been established to predict the fibre diameter and analysed by introducing the numerical computation results of air-jet flow field of the flat narrow slot passage of the aerodynamic device. The influence of density and specific heat capacity of polymer melt at constant pressure changing with polymer temperature on the fibre diameter have been studied. The effects of spunbonding processing parameters and drafting assembly design parameters on the fibre diameter have been discussed. A lower polymer throughput rate, higher polymer melt temperature, higher primary air temperature, higher air initial speed, medium smaller venturi gap, higher air suction speed, higher quench pressure, smaller highness of the drafting segment, larger length of the drafting segment, larger length of jet orifice of the drafting assembly, and bigger highness of jet orifice of the drafting assembly are found to be beneficial to the air drawing of spunbonding polymer melt as they produce finer fibres. The predicted fibre diameters agree with the experimental data. The findings show great prospects for this research in the field of computer assisted design of spunbonding process, technology and equipment.