Hand-Related Mechanical Behavior of Enzyme-Treated Yarns

Abstract

This work evaluates changes in the low-stress mechanical behavior of 100% cotton and cotton/polyester yarns after treatment with a cellulase enzyme. The yarns made from the same fiber stock on four different spinning systems are reeled into skeins, and the skeins are enzyme treated under identical conditions. The compression and bending properties of both treated and untreated yarns are measured to understand the influence of enzyme treatment on the hand-related mechanical behavior of the structurally different yarns. The treated cotton yarns representing different spinning systems show widely different weight losses, suggesting that both fiber erosion and fiber separation from the yarn may be contributing to the observed weight losses. Irrespective of the structural differences, most treated yarns show reduced compressive resilience, greater thickness compression, higher compression energy, and reduced linearity of the load versus compression curve, all of which indicate improved compressive softness. Most treated yarns also show reduced bending stiffness, suggesting improved yarn flexibility. The extent of changes in yarn properties is different for different yarns. Thus, the OE friction yarn accounts for the maximum change in hand-related mechanical properties among the cotton yarns, while the air-jet yarn accounts for the maximum change among the polyester/cotton yarns, suggesting that the treatment probably offers maximum tactile benefit for the yarns and fabrics representing these two spinning systems. The overall changes in the properties of the treated yarns suggest that optimally engineered woven and knitted fabrics made from these yarns will feel softer and more flexible.