Inverse relaxation in spun yarns

Abstract

Abstract This paper presents some experimental data on inverse relaxation exhibited by yarns spun from cotton, polyester, viscose rayon, and jute fibers. Inverse relaxation (IR) is the building up of tension in a viscoelastic material that has been allowed to recover a part of the initial extension it is subjected to. The IR index defined as a measure of the extent of this property has been determined at various levels of extension. A qualitative explanation of the results based on the fiber model proposed by Vitkauskas and Matukonis is also given.