Adsorption of alkyl-dimethyl-benzyl-ammonium chloride on differently pretreated non-woven cotton substrates

Abstract

The adsorption of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC), a cationic surfactant commonly employed as an antimicrobial agent, on greige, alkaline scoured, and bleached non-woven cotton fabrics was investigated at varying surfactant concentrations using ultraviolet-visible spectroscopy. Results show greige cotton non-wovens adsorb roughly three times the ADBAC in aqueous solution than bleached cotton and 1.5 times more than scoured cotton non-wovens. At a constant ADBAC concentration of 0.625 g/l, the rate of surfactant adsorption approached equilibrium after 35 minutes in all fabrics studied. Increasing surfactant concentration increased the total mass of ADBAC exhausted onto the cotton fabrics at equilibrium. Adsorption of ADBAC on cotton fabrics can be attributed to bulk entrapment, dispersion forces, and hydrophobic and electrostatic interactions. Polyester fiber was blended with greige and bleached cotton fibers to further elucidate the adsorption of ADBAC. A linear decrease in the amount of surfactant exhausted was observed as the amount of polyester added to the blend was increased. This indicates that the adsorption of ADBAC on cotton fabrics is primarily an effect of surface interactions of the cotton fiber with the surfactant molecules rather than absorption via bulk entrapment. The results of this research can aid in the development of cotton-based antimicrobial wipes.