Electropositive Cotton

Abstract

Raw and bleached cotton threads were cationized with 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride (CHPTAC). It is known that cotton is electronegative in aqueous solutions and repels anions making the adsorption of anion particles difficult such as dyes and fluorescent brighteners. In such a way modified cotton is electropositive in the entire pH-range, so better attracting electronegative particles of dyes and finishing agents. Electro-kinetic or zeta potential of the cationized cotton thread was measured by the zeta potential method of streaming current and using the Helmholtz-Smoluchowsky equation in the electro-kinetic analyzer (EKA, A. Paar) in a cylindrical cell adjusted for measuring textile fibres. Measurements were carried out depending on the pH-value of the electrolyte solution (10-3 mol/dm3 KC1). The zeta potential of the treated cotton is more positive by 10 - 15 mV in the whole pH-range. Cationized bleached cotton is substantially more positive than cationized raw cotton owing to a higher reactivity of cellulose with 3-chloro-2-hydroxy-propyl-trimethyl ammonium chloride. Since cotton was modified in the severe conditions of high alkalinity, changes in breaking force and elongation at break were investigated.