Hydroxysultaines are chemical compounds used in high-foaming

shampoo Shampoo () is a hair care product, typically in the form of a Viscosity, 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 ...

s, bath products and shower gels especially in conjunction with ether

sulfate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ...

s and alkyl sulfates. They are also used in industrial applications where high, stable foam is required. Chemically, hydroxysultaines are

zwitterionic In chemistry, a zwitterion ( ; ), also called an inner salt or dipolar ion, is a molecule that contains an equal number of positively- and negatively-charged functional groups. : With amino acids, for example, in solution a chemical equilibrium wil ...

, typically containing covalently linked positive and negative ions.

Synthesis

Hydroxysultaine is prepared industrially by the reaction of

sodium bisulfite Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite in fact is not a real compound, but a mixture of salts that dissolve in water to give solutions ...

with epichlorohydrin to give the sodium salt (sodium 1-chloro-2-hydroxypropane sulfonate). This is similar to the synthesis of isethionate, which is also used as a 'head-group' in surfactants. It is typically combined with the rest of the surfactant molecule via a

Menshutkin reaction In organic chemistry, the Menshutkin reaction converts a tertiary amine into a quaternary ammonium salt by reaction with an alkyl halide. Similar reactions occur when tertiary phosphines are treated with alkyl halides. The reaction is the meth ...

with a

tertiary amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such ...

Properties

Hydroxysultaines are also compatible with cationic surfactants and are stable over a wide pH range in soft or

hard water Hard water is water that has high mineral content (in contrast with "soft water"). Hard water is formed when water percolates through deposits of limestone, chalk or gypsum, which are largely made up of calcium and magnesium carbonates, bicarbo ...

. In addition to being used as a surfactant, hydroxysultaines are often used as

antistatic agent An antistatic agent is a compound used for treatment of materials or their surfaces in order to reduce or eliminate buildup of static electricity. Static charge may be generated by the triboelectric effect or by a non-contact process using a high ...

Examples

Examples include: * ISOTAINE LAPHS – Lauramidopropyl hydroxysultaine; derived from (C12:0)

lauric acid Lauric acid, systematically dodecanoic acid, is a saturated fatty acid with a 12-carbon atom chain, thus having many properties of medium-chain fatty acids. It is a bright white, powdery solid with a faint odor of bay oil or soap. The salts and ...

. * ISOTAINE CAPHS –

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 ...

;

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 w ...

is from a mixture of coconut fatty acids, 50% derived from (C12:0)

. * ISOTAINE OAPHS – Oleamidopropyl hydroxysultaine;

oleamide Oleamide is an organic compound with the formula CH3(CH2)7CH=CH(CH2)7CONH2(. It is the amide derived from the fatty acid oleic acid. It is a colorless waxy solid and occurs in nature. Sometimes labeled as a fatty acid primary amide (FAPA), it is ...

is from a

monounsaturated In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple est ...

omega-9 fatty acid Omega-9 fatty acids (ω−9 fatty acids or ''n''−9 fatty acids) are a family of unsaturated fatty acids which have in common a final carbon–carbon double bond in the omega−9 position; that is, the ninth bond from the methyl end of the fat ...

lipid number In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, fr ...

of 18:1

cis Cis or cis- may refer to: Places * Cis, Trentino, in Italy * In Poland: ** Cis, Świętokrzyskie Voivodeship, south-central ** Cis, Warmian-Masurian Voivodeship, north Math, science and biology * cis (mathematics) (cis(''θ'')), a trigonome ...

-9, formula CH₃(CH₂)₇CH=CH(CH₂)₇COOH. * ISOTAINE TAPHS – Tallowamidopropyl hydroxysultaine;

tallow Tallow is a rendered form of beef or mutton fat, primarily made up of triglycerides. In industry, tallow is not strictly defined as beef or mutton fat. In this context, tallow is animal fat that conforms to certain technical criteria, includ ...

is a mixture of fatty acids derived from beef or mutton fat, * ISOTAINE EAPHS – Erucamidopropyl hydroxysultaine;

erucic acid Erucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1ω9. It has the chemical formula CH3(CH2)7CH=CH(CH2)11COOH. It is prevalent in wallflower seed and other plants in the family Brassicaceae, with a reported content of 20 to 54% i ...

is a monounsaturated omega-9 fatty acid, denoted 22:1ω9. * ISOTAINE LHS – Lauryl hydroxysultaine; lauryl refers to fatty acid, lipid number C12:0

References

{{Reflist Household chemicals Zwitterionic surfactants Antistatic agents