Combining Mechanical Tension with Natural-Fiber-Welding Treatments of Cellulose Yarns

Understanding the combined effect of applied tension and polymer mobilization is vital both for controlling sample contraction during "natural-fiber welding" (NFW) experiments as well as for designing scaled-up NFW processes that rely upon tension for pulling yarn and cloth stocks through a continuous treatment apparatus. A preliminary set of tests evaluated the effect of applying tension in the axial dimension during NFW treatments of yarns. These tests with a ~0.4 mm diameter two-ply linen yarn show that when compared to untreated yarn, NFW combined with tension increases Young's modulus by a factor of 1.68 while NFW alone increases Young's modulus by a factor of 1.44. Any effects of either NFW combined with tension or NFW alone were not observed with a ~0.2 mm diameter three-ply mercerized cotton yarn.