Fiber-to-Yarn Strength Translation of Acrylic Spun Yarns

A method is described for accurately determining the ultimate tenacity of an acrylic yarn and its fiber-to-yarn strength translation efficiency. Both of these values are essentially independent of the nonuniformity of the denier of the yarn. The method con sists of determining the denier of thin segments of yarn with the Uster Evenness Tester and then finding the tensile strength of these same yarn segments with the Instron Tensile Tester. Differences between ultimate yarn tenacities in these thin yarn sections and tenacities based on yarn skein and single-end strengths are also examined.