In general, the main cationic part is an amine salt or a quaternary ammonium hydrophilic group. The anionic part generally contains a carboxylate, sulfonate, phosphate hydrophilic group. Amphoteric surfactants generally are classified into two types: pH-sensitive surfactants and non-ph-sensitive surfactants.
The aqueous solution of former has different dissociation degrees in different pH values. When it is alkaline, it exhibits anionic surfactants agent properties while if it is acidic, it exhibits cationic surfactant properties and upon being neutral, it shows non-ionic surfactant properties.
This kind of surfactants has isoelectric point which is a point of the cationic type and anionic type. At this point, the amino acid type amphoteric surfactant precipitates. Other types of amphoteric surfactants such as N- alkyl betaine type and hydroxy-imidazoline shows cationic characteristic based on acidicity. Sulfonic acid type betaine and phosphonyl group betaine are other examples of amphoteric surfactants which significantly used in shampoos; at all ranges of pH values, they exhibit anionic properties.
The lecithin which is contained in egg yolk, is the only ionic surfactant that can be used in the food industry and is almost insoluble in water with excellent emulsifying properties of oil. Amphoteric surfactants generally have antibacterial properties, low toxicity, excellent resistance to hard water, and excellent compatibility with various kinds of surfactants.
Table 2 Activity of the composite material in benzene alkylation with different olefins. Hence, they have various applications in detergent industry such as powdered and liquid cleaning agents and shampoos. Another example of amphoteric surfactants is the quaternized fatty acid amides glycine possessing mild properties and almost no irritating effect and as a result it can be used in baby shampoos.
One of the well-known foaming agents of shampoo powder is lauryllactam imidazolium salts. Another most used amphoteric surfactant is the amido propyl betaine contained in coconut and has the ability of using in mild shampoos and skin cleansers.
Amphoteric surfactants generally are rarely used alone and are often used with fatty alcohol sulfates. This combination gives rise to improve the solubility, increase the viscosity and the foam stability reduce and the irritation property. Amphoteric surfactants also have ability to be used in other applications such as metal rust agent and the antistatic agents of synthetic fiber.
Because of the high cost, it applications are subject to certain restrictions. In recent years, amphoteric surfactants have drawn significant attention and as a result have had rapid development. Another group of surfactants which are mostly used in detergents are non-ionic surfactants. Because of their voluntary or legal limitations of their appliction, at present, alkylphenol ethoxylates APE are only of restricted importance for cleaning detergents. In non-ionic surfactants generally the bacterial toxicity is very low, as a result their inhibitory effects to the bacterial biocenosis in wastewater treatment plant are rather improbable.
It is noteworthy that the aquatic toxicity of non-ionic surfactants possesses some general rules, so that with the increase in alkyl chain length and hydrophobicity of the molecule the toxicity increases, while the influence of the poly ethoxylate chain length is not of prime importance except for long-chain ethoxylates which exhibits a highly reduced ecotoxicity. The authors gratefully acknowledge the financial support from the Padideh Shimi Gharb Industrial Company.
This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and build upon your work non-commercially. Withdrawal Guidlines. Publication Ethics. Withdrawal Policies Publication Ethics. Open Access Journal of. Mini Review Volume 3 Issue 3. Figure 1 The places from which samples of the experiment were gathered.
Figure 4 Schematic illustration of the LAB production from normal paraffin. Alkenes Alkene con version wt. Figure 8 Examples of Amphoteric surfactants. F Friedli. Detergency of specialty surfactants, CRC Press. Augustin, Schonfeldt Nikolaus. Aqueous detergent-inorganic builder concentrates. Patent No. O'brien, Thomas P, Lawrence Benjamin.
The answer is yes, there are four different types of surfactants which are nonionic, anionic, cationic, amphoteric. These surfactants differ in composition and polarity. Surfactants also known as surface active agents, are used to lower the surface tension between liquids. The four different types of surfactants are all used to lower surface tension, but as they have differing compositions, they do serve different purposes. The various applications surfactants can be used in are vast as surfactants can be used as emulsifiers, wetting agents, foaming agents, anti-foaming agents, and dispersants.
Products including inks, soaps, detergents, waxes, paints and so much more require some type of surfactant for production. Surface and interfacial tensions play a key role in that. The net force, which effectively aims to keep the liquid together, is called surface tension. Surfactants are used in many industrial fields. Characterization of surfactants is thus important to optimize their performance and the products they are applied to.
Surface and interfacial tension measurements offer versatile method to study the properties and behavior of the surfactant solution. Contact Sign in. Start Menu. Sign in. Menu Products. Products Menu. Product category. Surfactant basics As said, surfactants are amphiphilic molecules that have hydrophobic and hydrophilic parts. Surfactants absorb at interfaces Because of their amphiphilic nature, surfactants absorb at the air-water or oil-water interface.
Topics: Surface tension. Related products. Explore the blog. You have only scratched the surface.
0コメント