Influence of Twist and Thermal Treatments on Characteristics of Acrylic-Polypropylene Blended Yarns

40-45<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:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Yarns spun from a majority of polypropylene fibres showed high strength and low extension. The yarn breaking strength tended to increase after boiling-water treatment. Thermal treatments had no significant effect on either unevenness or imperfections. Boiling-water treatment caused a higher yarn residual shrinkage than heating at various temperatures.