Effect of spandex filament draw ratio on elastic core spun yarn properties in friction spinning

Abstract

The aim of the present study is to produce elastic core/cotton spun yarns in a friction spinning (Dref-II) system and then to investigate the effect of spandex filament draw ratio on the physical and mechanical properties of produced yarns. First, a positive feed device was designed and developed to adjust the spandex draw ratio and then mounted on the friction spinning machine. To maintain a constant yarn count at various draw ratios, the proportion of cotton sheath fibers should be increased. The yarns with larger proportions of cotton fibers showed lower twist. The elastic core spun yarns have lower hairiness in comparison with 100% cotton yarns in the present experiments. The theoretical and experimental results indicate that the tenacity of elastic core spun yarn increases as the spandex draw ratio increases. While the elongation of the elastic core spun yarns is the same as 100% cotton yarn at low spandex draw ratios of less than 3.75, when the spandex draw ratios exceed 3.75, the elongation of the elastic core spun yarn increases sharply.