Adsorption of a fabric conditioner on cellulose nanocrystals: synergistic effects of surfactant vesicles and polysaccharides on softness properties

Abstract

Concentrated fabric conditioners are water-based formulations containing 10 wt. % of cationic surfactants that are deposited on textile fibers during the rinse cycle in a washing machine to make them smoother and softer to touch. In topical formulations, the concentration of cationic surfactants is reduced by half, this reduction being compensated by the addition of environmentfriendly polysaccharides. Using atomic force microscopy (AFM), quartz crystal microbalance with dissipation (QCM-D) and ellipsometry, the deposition of formulations with or without polysaccharides on model cellulose substrates is studied. We found that 180 nm long cellulose nanocrystals (CNCs) deposited by spin-coating on amorphous silicon dioxide or on quartz crystal sensors provide a good model of cellulose surfaces. QCM-D results reveal strong electrostatic interactions of the surfactant vesicles and polysaccharides with the CNC layer. In the presence of polysaccharides, the adsorbed quantities are less (by 60%) than the sum of the respective amounts of each component, the structure of the interface being however more homogenous and rigid. This outcome suggests that surface techniques coupled with CNC coated substrates are promising for studying interactions of current formulations with cellulose surfaces.

Advanced Eco-Friendly Formulations of Guar Biopolymer-Based Textile Conditioners

“…After drying, only fluorescent fibers and patches stuck on the fibers can be seen. These findings are consistent with results presented before, which show the strong interaction of guar polymers with CNC [ 37 , 39 ]. Our proposed mechanism showing the deposition of softener vesicles along with bilayers onto cotton fibers in water (conditions in washing machine) and the vesicles transformation to bilayers after drying is schematically represented in Figure 9 f. In conclusion, the proposed methodology based on fluorescent microscopy allow for the visualization of the product deposition and the evaluation of the softener performance and could be applied to elucidate the adsorption of other household or personal care products on solid surfaces.…”

“…Cotton fabrics treated with the softener were further investigated by scanning electron microscopy. The results presented here, together with those reported previously [ 36 , 37 , 39 ], show that the addition of minor amounts of natural polymers can reduce the amount of surfactants in conditioners and allow for formulations with a reduced environmental impact. This approach can facilitate the design of a class of sustainable home- and personal-care products.…”

“…The CNC fibers were shown to adsorb onto the TEQ vesicles in water. This procedure has been further confirmed by quartz crystal microbalance (QCM) [ 39 ]. Such deposition of intact vesicles was viewed also on cotton fibers through the treatment of cotton fabrics with aqueous dispersion of labeled TEQ.…”

“…Interaction of CNC with softener components (esterquat, HP-Guar, C-Guar) separately or in various combinations was followed by dynamic light scattering (DLS), zetametry and microscopy in the bulk and revealed strong interaction between CNC and esterquat or C-Guar due to electrostatics. Quartz crystal microbalance with dissipation (QCM-D) studies revealed that esterquat vesicles adsorb on CNC substrate and the guar biopolymers deposit with the vesicles on the CNC surfaces, the adsorption being more homogeneous and rigid in presence of polymers [ 39 ]. Our results indicated that polymers act synergistically with vesicles, enhancing the product efficiency.…”

Adsorption of Fragrance Capsules onto Cellulose Nano- and Micro-Cellulose Fibers in Presence of Guar Biopolymers

“…Although conditioners have been used for decades, only recent studies have addressed the deposition and softening mechanisms. Pertaining to the interaction with fabrics, it is now recognized that the surfactant vesicles spontaneously adsorbed to fibers in the wet state [6,7,13,14]. Upon slow evaporation of water and drying, the vesicles break up to form a surfactant supported bilayer that coats the textile fibers [8].…”