Mechanical behaviour of rotor-spun jute-viscose blended yarns at different twist levels

Abstract

<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:calibri;mso-bidi-theme-font:minor-latin;="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">The jute-viscose blended yarns, with blend ratios 50/50 and 25/75, were spun using different twist levels in a laboratory model rotor spinning machine and the effect of twist variation on the tensile characteristics of these yarns was studied. The yarn tenacity increased as twist decreased and reached a maximum value at the lowest spinnable twist, while the yarn breaking extension decreased first and then increased with increase in twist. The increased percentage of jute in rotor-spun jute-viscose yarn resulted in a decrease in both its tensile strength and breaking extension while it helped to obtain an improved initial modulus. Based on the results obtained, the structural mechanics of these yarns has been proposed. In the low twist region, the mechanics is governed by both the low-twisted inner core and the entangled fibres in its outer sheath. But, in high twist region, as yarn develops adequate cohesion the mechanics is dominated by the fibre obliquity effect.</span>