A foaming agent is a material such as a

surfactant Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsion#Emulsifiers , ...

or a

blowing agent A blowing agent is a substance which is capable of producing a cellular structure via a foaming process in a variety of materials that undergo hardening or phase transition, such as polymers, plastics, and metals. They are typically applied wh ...

that facilitates the formation of foam. A surfactant, when present in small amounts, reduces

surface tension Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension is what allows objects with a higher density than water such as razor blades and insects (e.g. water striders) t ...

of a liquid (reduces the work needed to create the foam) or increases its colloidal stability by inhibiting

coalescence Coalescence may refer to: * Coalescence (chemistry), the process by which two or more separate masses of miscible substances seem to "pull" each other together should they make the slightest contact * Coalescence (computer science), the merging o ...

of bubbles. A blowing agent is a gas that forms the gaseous part of the foam.

Surfactants

Sodium laureth sulfate, or sodium lauryl ether sulfate (SLES), is a

detergent A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are m ...

and

found in many personal care products (

soap Soap is a salt of a fatty acid used in a variety of cleansing and lubricating products. In a domestic setting, soaps are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are us ...

shampoo Shampoo () is a hair care product, typically in the form of a viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product into the ...

toothpaste Toothpaste is a paste or gel dentifrice used with a toothbrush to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it is an abrasive that aids in removing dental plaque and food from the teeth, ...

s, etc.). It is an inexpensive and effective foamer.

Sodium lauryl sulfate Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula . It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium s ...

(also known as sodium dodecyl sulfate or SDS) and ammonium lauryl sulfate (ALS) are commonly used alternatives to SLES in consumer products.Sodium Laureth Sulfate POE(2). Chemical Land 21, Seoul, Korea
Product Identification
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Co-surfactants

Surfactants which are less effective at foam production, may have additional co-surfactants added to increase foaming. In which case, the co-surfactant is referred to as the foaming agent. These are surfactants used in lower concentration in a

system than the primary surfactant, often the

cocamide Cocamide is a mixture of amides manufactured from the fatty acids obtained from coconut oil. As coconut oil contains about 50% of lauric acid, in formulas only the 12-carbon chains tend to be considered. Therefore the formula of cocamide can be wr ...

family of surfactants. Cocamide foaming agents include the nonionic

cocamide DEA Cocamide DEA, or cocamide diethanolamine, is a diethanolamide made by reacting the mixture of fatty acids from coconut oils with diethanolamine. It is a viscous liquid and is used as a foaming agent in bath products like shampoos and hand soaps, a ...

and cocamidopropylamine oxide, and the zwitterionic

cocamidopropyl betaine Cocamidopropyl betaine (CAPB) is a mixture of closely related organic compounds derived from coconut oil and dimethylaminopropylamine. CAPB is available as a viscous pale yellow solution and it is used as a surfactant in personal care products an ...

and

cocamidopropyl hydroxysultaine Cocamidopropyl hydroxysultaine (CAHS) is a synthetic amphoteric surfactant from the hydroxysultaine group. It is found in personal care products (soaps, shampoos, lotions etc.). It has uses as a foam booster, viscosity builder, and an antistatic ...

Blowing agents

There are two main types of blowing agents: gases at the temperature that the foam is formed, and gases generated by chemical reaction.

Carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...

pentane Pentane is an organic compound with the formula C5H12—that is, an alkane with five carbon atoms. The term may refer to any of three structural isomers, or to a mixture of them: in the IUPAC nomenclature, however, pentane means exclusively the ...

, and chlorofluorocarbons are examples of the former. Blowing agents that produce gas via chemical reactions include

baking powder Baking powder is a dry chemical leavening agent, a mixture of a carbonate or bicarbonate and a weak acid. The base and acid are prevented from reacting prematurely by the inclusion of a buffer such as cornstarch. Baking powder is used to increas ...

, azodicarbonamide, titanium hydride, and isocyanates (when they react with water).

References

* {{E number infobox 990-999, state=collapsed Surfactants Foams Building materials

Surfactants

Co-surfactants

Blowing agents

See also

References