Cotton Yarns in Continuous Wet Processing Engineering
Continuous wet processing of cotton yarns demands precise control of yarn structure, swelling draft, liquor application, and transport tension to assure performance.
Yarn Wet Modulus
Tensile Resistance
Elastic behavior under wet conditions characterizes the resistance of a textile yarn to stretching forces while saturated with water. The term yarn wet modulus denotes this mechanical property, which is calculated as the ratio of tensile stress to strain when the yarn is tested in a fully wetted state. This value acts as a differentiator between conventional and high-performance regenerated cellulosic fibers.
Moisture Sensitivity
Water absorption breaks down the internal hydrogen bonds within cellulosic fibers, reducing their crystalline stability and stiffness. High-wet-modulus fibers, such as modal, retain more of their structural integrity and resist stretching when wet, unlike standard viscose.
Fabric Shrinkage
Low wet modulus values lead to severe fabric deformation and shrinkage during commercial laundering. Garments made from yarns that stretch easily when wet will lose their shape and fail to recover during drying.
Dynamic Measurement
Laboratory testing utilizes a modified tensile tester equipped with a water bath or wetting device to keep the yarn saturated during extension. The tester records the stress-strain curve at a constant elongation rate, measuring the force required for a specific wet extension. This measurement assists weaving factories in predicting fabric stability during continuous wet processing and home washing.