Empirical modelling of filament area in melt extruded net structures

Abstract

A series of melt extruded net structures based upon Taguchi’s experimental design methods has been produced from patented Netlon process using square and trapezoidal die slots and a methodology is developed to analyse the extruded samples such that the filament cross-sections could be obtained without inflicting damage. The empirical models for the cross-sectional area of the filaments have been formulated with the main process parameters, viz. extruder speed, take-up speed, die rotational speed, melt flow index (MFI) and temperature. It is observed that the cross-sectional area of the filament mainly depends upon the extruder speed and take-up speed. While MFI has a moderate effect, the temperature and die rotation have negligible effect on filament cross-sectional area. Furthermore, another set of filaments has been produced from laboratory melt extruder, excluding the effect of die rotation. The results show that the influence of process parameters on the filament area is similar to that observed for the net structures produced from the Netlon process. Effects of die swell on the filament cross-sectional area have also been observed and analysed.