Mechanical damage to estabragh fibers in the production of thermobonded layers

摘要

Estabragh (Asclepias procerais) fibers are natural, hollow fibers, and the mechanical behavior of these fibers plays a major role in mechanical processing. This work explores the mechanical behavior of estabragh fibers in three different areas-tensile failure, carding behavior, and the construction of nonwoven layers-and reports the main barriers in the spinning process of these fibers. In the first step, a typical stress-strain curve of estabragh fibers is plotted. Fractography of the broken ends by scanning electron microscopy shows the granular nature of the fracture. The likely mechanism of tensile failure is discussed and compared with the fracture of cotton fibers under tensile loading. In the second stage, the carding behavior and likely mechanism of fiber damage during the carding pro-cess of estabragh fibers are studied. Both qualitative and quantitative studies show that estabragh fibers experience serious damage during the carding process. The effect of the hollowness of the fibers on their mechanical properties is discussed as well. In the final approach, thermobonded layers of two different blends of estabragh fibers and bicomponent poly(ethylene terephthalate) fibers are produced. Some properties of the produced layers, including moisture absorption, ultraviolet absorption, and bending length, are reported. (c) 2008 Wiley Periodicals, Inc.