Anionic surfactants laundry detergents

Sodium dodecylbenzenesulfonate is undoubtedly the anionic surfactant used in the greatest amount because it is the basic component in almost all laundry and dishwashing detergents in powder and liquid forms. However, alcohol and alcohol ether sulfates are the more versatile anionic surfactants because their properties vary, with the alkyl chain, with the number of moles of ethylene oxide added to the base alcohol and with the cation. Consequently, alcohol and alcohol ether sulfates are used in almost all scientific, consumer, and industrial applications. 

Ether carboxylates are used not only in powdered detergents but in liquid laundry detergents for their hard water stability, lime soap dispersibility, and electrolyte stability they improve the suspension stability and rheology of the electrolyte builder [130,131]. Formulations based particularly on lauryl ether carboxylate + 4.5 EO combined with fatty acid salt and other anionic surfactants are described [132], sometimes in combination with quaternary compounds as softeners [133,163]. Ether carboxylates show improved cleaning properties as suds-controlling agents in formulations with ethoxylated alkylphenol or fatty alcohol, alkyl phosphate esters or alkoxylate phosphate esters, and water-soluble builders [134]. 

From the anionic surfactants (Table 1.1) the most relevant is LAS with an annual global production volume of more than 3 X 1061 in 2001. LAS has a wide application because of its excellent detersive properties and cost-performance ratio. Commercial LAS is applied mainly in the formulation of powder and liquid laundry detergents. The calcium salts are used as an emulsifier in pesticide formulations their amine salts are used in dry cleaning and as degreasing agents in the metal industry [14]. 

Another important group of anionic surfactants are AESs, which are used in laundry and cleaning detergents as well as in cosmetic products. Characteristic properties of AESs are the ability to function in hard water, high foam capacity and low irritation to skin [16]. 

Nonionic surfactants are also used in substantial amounts in laundry detergents and in automatic dishwashing detergents, both applications reflecting in particular their generally lower sudsing characteristics than the anionics. Commercially important examples uf the nonionics include the alkyl ethoxylates, the ethoxylated alkyl phenols, the fatly acid ethanol amides, and complex polymers of ethylene oxide, propylene oxide, and alcohols. 

Non-ionic surfactants are neither positively nor negatively charged but instead they have several oxygen atoms at the head end of the molecule, generally in the form of a series of ->ethoxy groups.711 They produce less foam than anionic surfactants and are used in low temperature laundry detergents because they work well even at 30 °C. 

Cationic surfactants are not used as the primary surfactant in laundry detergents, as this responsibility falls on the commodity surfactants such as linear alkyl benzene sulfonates, ethoxylated alcohols and alkyl sulfates. Nevertheless, over the past 20 years there has been extensive art claiming the use of cationics to improve the performance of their anionic counterparts [67,69,70]. A combination of an alkyl phosphate (AP) and (note APE = alkyl... 

Amphoteric surfactants. These compounds have the characteristics of both anionic detergents and cationic fabric softeners. They tend to work best at neutral pH, and are found in shampoos, skin cleaners, and carpet shampoos. They are very stable in strong acidic conditions and are favorably used with hydrofluoric acid. For example, compounds of alkyl-betain or alkylsulfobetaine type possess both anionic and cationic groups in the same molecule even in aqueous solution. These surfactants are rarely employed in laundry detergents because of their high costs [3, 4]. 

This section briefly describes the anionic and nonionic surfactants commonly used in commercial HDLD formulations. Cationic surfactants, although used on a large scale, are found predominantly in rinse-added fabric softener products. LAS, alcohol ethoxylates, and alkyl ether sulfates are three of the most widely used surfactants in liquid laundry detergents [44], Recently, various external considerations, such as environmental pressures, have prompted manufacturers to change their surfactant mix to include newer natural-based surfactants [45-47], including alkyl polyglucosides (Henkel) [48],... 

The hydrophilic groups of anionic surfactants consist in most cases of sulfonate, sulfate, or carboxyl groups (Table 30.1). Amongst them, LAS are produced in the largest quantities worldwide. These are mainly used in powdery and liquid laundry detergents and household cleaners. 

At the same time, surfactants like alkylbenzene sulfonates remain the most widely used basis for laundry detergents. Anionics remain the main products for making detergent compositions. Some of the application aspects of relatively new types of anionics (a-olefin sulfonates, sulfocarboxylic acids, alkyl phosphates etc.), whose commercial manufacture began in the 60-ties - 70-ties of the 20 century, are described by Stache [95]. The application of conventional types of nonionics like ethoxylated alcohols or alkyl phenols is presented in [13 -14], Alkyl polyglycosides were widely used in the last 5-8 years [96]. However, the main tendency in the development of new generation detergents is the use of surfactant mixtures in their optimum composition [97, 98]. 

Uses Whitener for cotton and other cellulosics surfactant in anionic and nonionic laundry detergents, dry bleaches, fabric softeners, commercial laundry prods. vise, control agent Trade Names Containing Uvitex NFW Liq. 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of SOx and Na20 Uses Whitener for cotton and other cellulosics surfactant in anionic and nonionic laundry detergents, dry bleaches, fabric softeners, commercial laundry prods. vise, control agent Trade Name Synonyms Eutex CBS [Aceto http //www.aceito.com], Tinopal CBS-X [Ciba Spec. Chems./Plastic Addit. http //WWW. cibasc. com]... 

The main cleaning agent in a typical home laundry detergent is the suifactant which in most domestic products will be either anionic or non-ionic in nature. Surfactants lower the surface tension of water allowing the fabric surface to be wetted out and assist... 

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