The adsorption of alkyl-dimethyl-benzyl-ammonium chloride onto cotton nonwoven hydroentangled substrates at the solid-liquid interface is minimized by additive chemistries

Authors: Hinchliffe, Doug; Condon, Brian; Slopek, Ryan; Reynolds, Michael

Submitted to: Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/17/2015
Publication Date: 1/2/2017
Citation: Hinchliffe, D.J., Condon, B.D., Slopek, R.P., Reynolds, M.L. 2017. The adsorption of alkyl-dimethyl-benzyl-ammonium chloride onto cotton nonwoven hydroentangled substrates at the solid-liquid interface is minimized by additive chemistries. Textile Research Journal. 87(1):70-80.

Interpretive Summary: Quaternary ammonium compounds (quats) are widely used at the industrial and consumer levels in disinfecting solutions and in disposable, disinfecting wipes. It is has been demonstrated that cotton substrates deplete quats from disinfecting solutions, thereby reducing the amount of quat deposited onto a hard surface for effective disinfection. The concentrations of quats required for disinfection are crucial in determining the levels required for a repeat use or single use situation. This is one reason for the lack of use of cotton staple fibers for wipes production, which is dominated by synthetic fibers such as polypropylene and polyester. Circumventing the incompatibility of quats with cotton has the potential to increase the consumption of cotton fibers in the wipes market and in other cotton-based disinfecting implements, thereby promoting a sustainable and biodegradable natural resource. Various conditions and chemicals that are known to effect quat adsorption onto a wipe substrate were examined in the presence of raw and scoured and bleached cotton wipes produced in-house by hydroentanglement. The results provided optimal conditions required in co-formulations to negate the depletion effect on quats in the presence of cotton substrates and will guide the development of an optimized quat co-formulation fully compatible with cotton-based nonwoven substrates.

Technical Abstract: Quaternary ammonium compounds, commonly referred to as quats, are cationic surfactants widely used as the active biocide ingredient for disposable disinfecting wipes. The cationic nature of quats results in a strong ionic interaction and adsorption onto wipes materials that have an anionic surface charge, such as cellulosic materials including cotton and rayon. The degree of adsorption of quats onto cotton nonwovens is affected by pretreatment of the substrate, more specifically whether it is a greige or a scoured and bleached fabric. In this research, we examine the effect of varying the chemical and physical properties of solutions on the adsorption of the quat alkyl-dimethyl-benzyl-ammonium chloride (ADBAC) on low-weight greige and scoured and bleached cotton nonwoven fabrics produced by hydroentanglement. At a constant surfactant concentration, the liquor ratio, pH, temperature, and concentrations of various electrolytes in the solution were varied and the amount of ADBAC exhausted from solution was determined over time using UV-vis spectroscopy. The results suggested that a more alkaline solution increased the amount of ADBAC adsorbed onto both greige and bleached cotton nonwovens, while a more acidic solution reduced ADBAC adsorption onto the cotton fabrics. Likewise, increasing the temperature and concentration of salts in the solution reduced the adsorption of ADBAC onto the cotton fabrics. The presence of nonionic surfactants or small quats also reduced ADBAC adsorption onto cotton fabrics in a concentration dependent manner. The results of this study will provide guidance for optimized chemical formulations for use with disposable disinfecting cotton-based wipes.