Effect of Varying Nonwoven Cotton Substrate and the Properties of the Surfactant Solution Upon the Adsorption of Aqueous Solutions of Alkyl-Dimethyl-Benzyl-Ammonium Chloride

The adsorption of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC), a cationic surfactant commonly employed as an antimicrobial agent, on greige, alkaline scoured, and bleached nonwoven cotton fabrics was investigated at varying surfactant concentrations using UV/vis spectroscopy. Results show greige cotton nonwovens adsorb roughly three times the ADBAC in aqueous solution than bleached cotton and 1.5 times more than scoured cotton nonwovens. At a constant ADBAC concentration of 0.625 g/L, the rate of surfactant adsorption approached equilibrium after 35 minutes in all fabrics studied. The adsorption of ADBAC on cotton nonwovens can be control by varying the chemical and physical properties of the surfactant solutions. Initial research shows that varying the liquor ratio, pH, temperature, and the concentration of electrolyte in the solution affects ADBAC adsorption. Adsorption of ADBAC on cotton fabrics can be attributed to a combination of bulk entrapment, dispersion forces, 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 resulting data is expected to aid in the development new cotton nonwoven products, such as disposable antimicrobial cotton based wipes, and new surfactant formulations designed specifically for cotton.