Variation in the level of metals on raw, scoured, and bleached varietal cotton samples produced in different locations

Authors: Fortier, Chanel; Delhom, Christopher; Dowd, Michael

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2019
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: It has been proposed that the surface metal composition of cotton fiber can affect fabric dyeability. Cotton fabrics are normally scoured and bleached to remove surface contaminants, including metals, prior to being dyed. While the metal content of raw cotton varies significantly, it is not known how variable the metal content of cotton fabrics are after they have been scoured and bleached. To better understand the likelihood that variation of metal levels affects the dying process, cotton fiber samples from different cotton varieties (grown in Lubbock, TX) and of one variety (PHY499) grown in different field locations were analyzed for metal content in the raw state, after scouring, and after bleaching. As expected, there were considerable differences in the levels of different metals in the raw cottons and the levels decreased as the fibers were scoured and then bleached. Potassium was largely removed by the treatments, but significant levels of calcium, magnesium, and phosphorus remained after the treatments. The variation (CV) of the different metals on the raw fiber were between 15 and 60% for the variety (PHY499) grown in different locations and between 15 and 20% for the different varieties grown in Lubbock, TX. In general, the CV of the same samples was greater after scouring and bleaching (40-60%), indicating that the variation in metal content was greater than observed by the raw fibers. Whether this variation is sufficient to affect dyeability of the fibers is being explored.