Mechanical Properties of Cotton/Polyester Yarns

Abstract

Samples of two cotton cultivars were spun with high- and normal-tenacity polyester staple fibers in cotton/polyester blend ratios of 100:0, 67:33, 50:50, 33:67, and 0:100. Stress-strain measurements provided tenacities, elongations, and breaking energies. Based on the stress-strain response of the pure cotton and pure polyester yarns, breaking energies were calculated for the yarn blends, with the assumption that the two different components did not interact. Differences between calculated and experimental values, which were maximum when the polyester content was about 60%, were attributed primarily to the interaction between the constituent cotton and polyester fibers. Support for this attribution was provided through measurements of energy lost when an oscillatory shearing motion was applied to 50-gram blended specimens of carded lap.