Impact of the Elastane Percentage on the Elastic Properties of Knitted Fabrics under Cyclic Loading

Abstract

Elastic knitted fabrics find numerous applications in the industry for compression stockings, sports and leisure wear, swimwear, ballet wear, etc. During its use, knitwear is subjected to dynamic loading due to body movements. The loading and unloading of the knitted fabric affect the size of the elastic region in which unrecovered deformation completely disappears. This paper deals with the influence of the elastane percentage in the knitted fabric on the elastic properties of the knitted fabric under dynamic loading. For this experiment, three types of yarn were used in different combinations: polyamide (PA), wrapped elastane yarn and bare elastane. The mentioned yarns were used to knit three different groups of plated weft-knitted fabrics (two yarns in a knitted fabric row): without elastane, knitted fabric with a percentage of wrapped elastane, and knitted fabric with a percentage of bare elastane. The percentage of elastane ranged between 0% and 43%. First, standard uniaxial tensile tests were performed on knitted fabric samples until breakage under static load. The force–elongation diagrams obtained are used to determine the elastic limit up to which Hook’s law applies. All knitted fabrics were cyclically tested to the elastic limit. From the obtained loading and unloading curves, unrecovered deformation (unrecovered elongation), elastic elongation and hysteresis index were determined and calculated. The results showed that the percentage of elastane significantly affects the size of the elastic region of the knitted fabric and has no effect on the hysteresis index. Therefore, it is necessary to optimize the elastane percentage for different knitted fabric designs to achieve the best dynamic recovery of the knitted fabric and to design a more stretchable knitted garment that fits the body as well as possible.

Investigating the effect of different filaments and yarn structures on mechanical and physical properties of dual-core elastane composite yarns

“…These differences could be due to the core-spun nature of the yarns where cohesion and slippage among constituent fibers and filaments influence the tenacity and elongation of the yarn. In another study, researchers reported that the extent of elongation of the knitted fabric was higher when bare elastane was used in the knitted fabric compared with wrapped elastane [ 14 ]. Fig.…”

“…The stretch and recovery properties of the elastane yarns are dependent on several factors such as elastane percentage in the yarn [ 14 ], elastane draft and elastane linear density [ 6 , 12 ], yarn structure [ 5 , 15 ], the position of the filament within the core [ 16 ], presence of single or dual-core filaments [ 17 ], process parameters [ 18 ], and the filament itself. Although the interest in dual-core yarns has increased, fewer research studies have explored the properties of different dual-core yarns [ 17 ].…”

Endowing textiles with self-repairing ability through the fabrication of composites with a bacterial biofilm

“…Being mechanically strong is crucial for clothing fabrics to withstand daily wear and have a long lifetime, so we conducted tensile tests on the textiles before and after biofilm integration to determine the Young’s moduli and the elongation at break of the materials. Given that textiles’ mechanical behaviors vary with the direction of stretching in tensile tests, we performed all the mechanical tests in this study in the course direction perpendicular to the textiles’ grainline, as jersey fabrics are more elastic in this direction than in the direction of wales 49 , 50 . The stress–strain curves illustrated the distinctive mechanical responses displayed by the composites prepared with different fabrication methods (Fig.…”

The effect of weft yarn type and elastomer yarn threading on the properties of elastic warp knitted fabrics. Part 1: Structure and elasticity

“…Senthilkumar et al 19 studied elastic behavior of cotton/spandex knitted fabric and its dependence to spandex input tension and linear density. There are some later works, [20][21][22] but most of them related to the elastic weft knitted fabric from core spun yarn used in sports garment.…”