Surfactants anionic, cationic, amphoteric

Of the four types of synthetic surfactants, anionic, cationic, amphoteric, and nonionic, the anionic surfactants provide maximum lather and hence are used as major components in liquid products. The active ingredients used in the major brands of liquid soaps are described by Dyer and Hassapis [6],... 

The hydrophilic portion of a surfactant may carry a negative or positive charge, both positive and negative charges or no charge at all. These are classified respectively as anionic, cationic, amphoteric (or zwitterionic ) or non-ionic surfactant. 

Therefore, there are four main groups of surfactants anionic, cationic, nonionic, and amphoteric[ 1 ]. 

A simple classification of surfactants, based on the nature of the hydrophilic group, is commonly used, with four main classes being distinguished anionic cationic amphoteric and nonionic. A useful technical reference here is McCutcheon [3], which is produced annually to update the list of available surfactants. A recent text by van Os et al. [4], hsting the physico-chemical properties of selected anionic, cationic and nonionic surfactants, has been published by Elsevier. 

Anionic, cationic, amphoteric, zwitterionic surfactants thickening agents benefit agents (silicones, fats and oils, vitamins, plant extracts, sunscreens, alkyl lactate, essential oils, etc.) small amount of soap... 

Chapter 1 gives a systematic view of different classes of surface active substances non-ionic, anionic, cationic, amphoteric and zwitter-ionic surfactants. For each class, the synthesis of a surfactant from different initial substances (including the reaction mechanisms, main production routes, conditions for the best performance etc.), and the chemical analysis of the product properties are summarised. Reference information about manufacturers, nomenclature... 

The free-radical addition of TFE to pentafluoroethyl iodide yields a mixture of perfluoroalkyl iodides with even-numbered fluorinated carbon chains. This is the process used to commercially manufacture the initial raw material for the fluorotelomer -based family of fluorinated substances (Fig. 3) [2, 17]. Telomeri-zation may also be used to make terminal iso- or methyl branched and/or odd number fluorinated carbon perfluoroalkyl iodides as well [2]. The process of TFE telomerization can be manipulated by controlling the process variables, reactant ratios, catalysts, etc. to obtain the desired mixture of perfluoroalkyl iodides, which can be further purified by distillation. While perfluoroalkyl iodides can be directly hydrolyzed to perfluoroalkyl carboxylate salts [29, 30], the addition of ethylene gives a more versatile synthesis intermediate, fluorotelomer iodides. These primary alkyl iodides can be transformed to alcohols, sulfonyl chlorides, olefins, thiols, (meth)acrylates, and from these into many types of fluorinated surfactants [3] (Fig. 3). The fluorotelomer-based fluorinated surfactants range includes noiuonics, anionics, cationics, amphoterics, and polymeric amphophiles. 

Vytfas and co-workers have reported successful titrations of large numbers of anionic, cationic, amphoteric and even nonionic surfactants using such electrodes. The paper cited [18] is a review with 38 references. The response appears to be sub-Nernstian, but when used as end-point indicators these electrodes exhibit potential jumps of up to 100 mV or more for very small increments of titrant. 

Active over the entire usable pH range (pH 2 through pH 12). Outstanding compatibility with acids, alkalis, hard water, soap lathers, electrolytes, and surfactants (anionic, cationic, nonionic, and amphoteric). 

Fluorocarbon surfactants have been prepared with various structures, consisting of perfluoroalkyl chains and anionic, cationic, amphoteric and poly(ethylene oxide) polar groups. These surfactants have good thermal and chemical stability and they are excellent wetting agents for low energy surfaces. 

Conventional anionic, cationic, amphoteric and nonionic surfactants are also used in cosmetic systems. Besides the synthetic surfactants that are used in preparing cosmetic systems such as emulsions, creams, suspensions, etc., several other naturally occurring materials have been introduced and there has been a trend in recent years to use such natural products more widely, in the belief that they are safer for application. 

Separation of two or more types of surfactants in cosmetics. To separate two or more types of surfactants in cosmetics involves using several detectors or columns as well as studying separation variables in particular pH. Kadono et al. (1987) proposed a reversed-phase LC method using a combination of the UV with RI as detector. A ratio of the UV/RI area versus a retention time that was specific to each surfactant. This method was applied to hair cleanser (shampoos and hair conditioners) containing anionic, cationic, amphoteric and nonionic surfactants. 

Uses Surfactant, wetting agent, penetrant, emulsifier in laundry detergents, tub and tile cleaners, metal cleaners, disinfectants and sanitizers Features Compat. with nonionic, anionic, cationic, amphoteric surfactants Properties APHA color 100 max. mild odor sp.gr. 0.99 pour pt. -5 C cloud pt. (1% aq.) 42 C flash pt. 182 C pH (1% aq.) 7 surface tens. (0.1%) 28 dynes/cm interfacial tens. (0.1% vs. mineral oil) 6 dynes/cm 100% act. 

Cationic, anionic, and amphoteric surfactants derive thek water solubiUty from thek ionic charge, whereas the nonionic hydrophile derives its water solubihty from highly polar terminal hydroxyl groups. Cationic surfactants perform well in polar substrates like styrenics and polyurethane. Examples of cationic surfactants ate quaternary ammonium chlorides, quaternary ammonium methosulfates, and quaternary ammonium nitrates (see QuARTERNARY AMMONIUM compounds). Anionic surfactants work well in PVC and styrenics. Examples of anionic surfactants ate fatty phosphate esters and alkyl sulfonates. 

Any hydrophobe can yield each of the main (i.e. anionic, cationic, nonionic or amphoteric) types of surfactant in much the same way as the same chromogenic system can be used in anionic, basic or disperse dyes. This will be demonstrated in the following sections, dealing with each class of surfactant, using the cetyl-containing (C16H33) hydrophobe. 

Since levelling agents are invariably surfactants, they may be anionic, cationic, nonionic or amphoteric in nature. Sometimes combinations of these are used. The chemical structure of commercial products is seldom revealed, however hence only general principles can be covered here. The main mechanisms by which levelling agents operate [337-341] are as follows ... 

The classification of surfactants in common usage depends on their electrolytic dissociation, which allows the determination of the nature of the hydrophilic polar group, for example, anionic, cationic, nonionic, and amphoteric. As reported by Greek [18], the total 1988 U.S. production of surfactants consisted of 62% anionic, 10% cationic, 27% nonionic, and 1% amphoteric. 

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