Dependence of Structural Characteristics of Polyamide Textured Yarns on the Parameters of the False Twist Yarn Texturing Process

Abstract

In the false twist texturing process, due to the action of mechanical forces and heat, a disorientation of structural elements happens at all levels of the supramolecular structure. These changes are related to changes in the texturing parameters and mechanical properties of yarn. In this paper, investigated is the effect of technical-technological texturing parameters in the false twist texturing process on the structure of PA6.6 yarns. POY multifilament PA6.6 with a fineness of 22f07x1 dtex was used as experimental material. The yarn was textured on a friction texturing machine - ICBT model FT 15 E3. The exiting yarn speed (Vi) changed as 600, 700, 800 and 900 m/min; the heater temperature (T) was 200, 210 and 220 °C, and the ratio of the disk surface speed to the linear yarn speed (D/Y) was 1.9 and 2.1. The values of strain were kept constant at 1.305 (tension in texturing zone) and 0,954 in the winding zone. Analysed were the density, degree of crystallinity, degree of orientation, single filament diameter, the content of -NH2 and -COOH end groups, and the total content of end groups. From the results obtained it can be seen that the effect of the heater temperature is more significant than that of Vi and D/Y on the structural characteristics analysed. Analysing the experimental results it was found that linear positive correlations were established between the texturing speed and end (-NH2) groups, the texturing speed and end (-COOH) groups and the texturing speed and the total content of end groups. The correlation factor between the process parameters and yarn structural characteristics analysed is determined.