Detergency amphoterics

Amphoteric L offers good detergency and superior wetting. When added to anionic or nonionic detergents. Amphoteric L will enhance foam stability. Amphoteric L is stable in both mildly alkaline and mildly acidic media. If stability is desired in highly acidic or alkaline media, one of the EXXON iminodipropionate amphoterics should be selected. 

Amphoteric Detergents. These surfactants, also known as ampholytics, have both cationic and anionic charged groups ki thek composition. The cationic groups are usually amino or quaternary forms while the anionic sites consist of carboxylates, sulfates, or sulfonates. Amphoterics have compatibihty with anionics, nonionics, and cationics. The pH of the surfactant solution determines the charge exhibited by the amphoteric under alkaline conditions it behaves anionically while ki an acidic condition it has a cationic behavior. Most amphoterics are derivatives of imidazoline or betaine. Sodium lauroamphoacetate [68647-44-9] has been recommended for use ki non-eye stinging shampoos (12). Combkiations of amphoterics with cationics have provided the basis for conditioning shampoos (13). 

Baby Shampoos. These shampoos, specifically marketed for small children, feature a non-eye stinging quaHty. The majority of the products in this category are based on an amphoteric detergent system a system combining the use of an imidazoline amphoteric with an ethoxylated nonionic surfactant has been successfiiUy marketed (15,16). The sulfosuccinates also have been suggested for baby shampoo preparation because of thek mildness... 

An unknown commercial detergent may contain some combination of anionic, nonionic, cationic, and possibly amphoteric surfactants, inorganic builders and fillers as weU as some minor additives. In general, the analytical scheme iacludes separation of nonsurfactant and inorganic components from the total mixture, classification of the surfactants, separation of iadividual surfactants, and quantitative determination (131). 

Protease performance is strongly influenced by detergent pH and ionic strength. Surfactants influence both protease performance and stabiUty in the wash solution. In general, anionic surfactants are more aggressive than amphoteric surfactants, which again are more aggressive than nonionic surfactants. 

Cocamidopropyl betaine is an amphoteric detergent, a detergent that can act as an acid or a base. It does not irritate the skin or mucous membranes. It is used to thicken shampoos, and to reduce the irritation that would result if only more irritating detergents were used. It has antibiotic effects, and is used in personal sanitary products. It also has antistatic properties, making it an effective conditioning agent in shampoos. 

In addition to the soaps and fatty acids, some bars contain cocamidopropyl betaine, a mild amphoteric detergent that is added to control irritation without decreasing suds or cleaning power, and benzine sulfonate detergents such as sodium dode-cylbenzinesulfonate. Other detergents, such as sodium isethion-ate and sodium cocoyl isethionate, are also common. 

Sodium isethionate is an amphoteric detergent used in detergent bar soaps. It makes a dense lather in addition to the lather made by the soap. It is nondrying and mild on the skin. It works equally well in soft or hard water. It is also an antistatic agent in shampoos. 

Sodium cocoyl isethionate is a related amphoteric detergent used in mild bath soaps, toothpastes, and baby soaps. 

The sulfated alkylbenzenesulfonamides (no. 7-8) and alkylaroylsulfo-propionates (no. 9) were found to be efficient lime soap dispersants [27]. Although the nonionics (nos. 10-11) had low LSDR values they did not potentiate the detergency of soap and exhibited some antagonism. Amphoteric surfactants with alkyl side chains from C12 to C18 (nos. 12-13) possessed the lowest LSDR values, ranging from 2 to 4. The amine oxide derived from an aromatic sulfonamide had a low LSDR of 5 close to that of amphoterics. 

Formulations based on soap and an amphoteric LSDA were superior in performance to those containing soap and anionic LSDA [29]. Whereas soap-anionic LSDA formulations could not tolerate the addition of sodium sulfate, a commonly used detergent diluent, the analogous amphoteric LSDA formulations tolerated addition of up to 20% Na2S04 quite well. Detergency performance of such formulations was equal or superior to that of a high-phosphate control. 

A surfactant can be grouped in one of the four classes - anionic, nonionic, cationic and amphoteric surfactants, depending on what charge is present in the chain-carrying hydrophilic portion of the molecule after dissociation in aqueous solution. Tab. 4.1 shows examples of surfactants most commonly used for detergents. 

Contrary to anionic and nonionic agents, they have poor detergency and are used more in the preparation of germicides, fabric softeners, and emulsifiers. Amphoteric surfactants are produced in much smaller amounts (5xl04 metric tons, near to 2% of the total production) [125] they are biodegradable and their ecotoxicological importance can be considered low. Their environmental occurrence up to know has been just occasional. 

Even if this class covers the smallest market segment, amphoteric surfactants still remain useful because of their unique properties, which justifies their comparably high manufacturing costs. Since they have partial anionic and cationic character, they can be compatible, under specific conditions, with both anionic and cationic surfactants. They can function in acid or basic pH systems and, at their isoelectric point, they exhibit special behaviour. Many amphoteric surfactants demonstrate exceptional foaming and detergency properties combined with antistatic effects. 

As in aqueous detergent solutions it has become customary to distinguish nonionic and ionic surfactants, thereby subdividing the latter into cationic and anionic surfactants. Some authors also include amphoteric surfactants in this group. Typical representatives of these surfactant types are given in Table 1. The distinction between... 

Explain the difference between anionic, cationic, neutral, and amphoteric detergents. 

Amphoteric surfactants have both a positive and a negative component at the water-attracting end. Amphoteric surfactants are used in washing-up liquids, but rarely in laundry detergents because they cost too much. The best known amphoteric surfactants are the cocamides. 

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