Mercerized and Crosslinked Cotton Yarns

Abstract

The effect of varying degrees of stretch on various cotton yarn properties during mercerization was studied. Scoured cotton yarns were slack mercerized in an aqueous solution of caustic soda, then restretched to 90%, 94%, 96%, 100%, and 103% of the original lengths. There was a considerable increase in strength and a decrease in elon gation. Mercerized and scoured yams were subjected to a crosslinking treatment with formaldehyde using the Form W and D processes. The mercerized yarns had a higher formaldehyde content but retained higher strength compared to scoured crosslinked yarn for both crosslinking processes. The mercerized yarn samples stretched to 103% showed the highest strength retention values after crosslinking for both the processes compared to other yams. The scoured yams crosslinked by the Form D bath process showed very low tenacity retention (42%), while the yam mercerized and stretched to 103% showed very high tenacity retention (90%). The relationships between strength and various other properties are also discussed. The higher retention of tenacity in mercerized crosslinked yam is attributed to the removal of weak points present in cotton and the more uniform structure capable of distributing stress along the fibers.