Ammonium lauryl sulfate

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Ammonium lauryl sulfate
Ammonium dodecyl sulfate.svg
Ammonium-dodecylsulfate-3D-balls-ionic.png
Names
IUPAC name
Ammonium dodecyl sulfate
Other names
• monododecyl ester, ammonium salt
• Ammonium dodecyl sulfate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.017.086 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/C12H26O4S.H3N/c1-2-3-4-5-6-7-8-9-10-11-12-16-17(13,14)15;/h2-12H2,1H3,(H,13,14,15);1H3 Yes check.svgY
    Key: BTBJBAZGXNKLQC-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C12H26O4S.H3N/c1-2-3-4-5-6-7-8-9-10-11-12-16-17(13,14)15;/h2-12H2,1H3,(H,13,14,15);1H3
    Key: BTBJBAZGXNKLQC-UHFFFAOYAS
  • [O-]S(=O)(=O)OCCCCCCCCCCCC.[NH4+]
Properties
C12H29NO4S
Molar mass 283.43 g/mol
Appearanceyellowish viscous liquid
Density 1.02 g/cm3
Boiling point 418 °C (784 °F; 691 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Ammonium lauryl sulfate (ALS) is the common name for ammonium dodecyl sulfate (CH3(CH2)10CH2OSO3NH4). The anion consists of a nonpolar hydrocarbon chain and a polar sulfate end group. The combination of nonpolar and polar groups confers surfactant properties to the anion: it facilitates dissolution of both polar and non-polar materials. This salt is classified as a sulfate ester. It is made from coconut or palm kernel oil for use primarily in shampoos and body-wash as a foaming agent. [1] [2] Lauryl sulfates are very high-foam surfactants that disrupt the surface tension of water in part by forming micelles at the surface-air interface.

Contents

Action in solution

Above the critical micelle concentration, the anions organize into a micelle, in which they form a sphere with the polar, hydrophilic heads of the sulfate portion on the outside (surface) of the sphere and the nonpolar, hydrophobic tails pointing inwards towards the center. The water molecules around the micelle in turn arrange themselves around the polar heads, which disrupts their ability to hydrogen bond with other nearby water molecules. The overall effect of these micelles is a reduction in surface tension of the solution, which affords a greater ability to penetrate or "wet out" various surfaces, including porous structures like cloth, fibers, and hair. Accordingly, this structured solution allows the solution to more readily dissolve soils, greases, etc. in and on such substrates. Lauryl sulfates however exhibit poor soil suspending capacity. [2]

Safety

ALS is an innocuous detergent. A 1983 report by the Cosmetic Ingredient Review, shampoos containing up to 31% ALS registered 6 health complaints out of 6.8 million units sold. These complaints included two of scalp itch, two allergic reactions, one hair damage and one complaint of eye irritation. [3] [4]

The CIR report concluded that both sodium and ammonium lauryl sulfate "appear to be safe in formulations designed for discontinuous, brief use followed by thorough rinsing from the surface of the skin. In products intended for prolonged use, concentrations should not exceed 1%".

The Human and Environmental Risk Assessment (HERA) project performed a thorough investigation of all alkyl sulfates, as such the results they found apply directly to ALS. Most alkyl sulfates exhibit low acute oral toxicity, no toxicity through exposure to the skin, concentration dependent skin irritation, and concentration dependent eye-irritation. They do not sensitize the skin and did not appear to be carcinogenic in a two-year study on rats. The report found that longer carbon chains (16–18) were less irritating to the skin than chains of 12–15 carbons in length. In addition, concentrations below 1% were essentially non-irritating while concentrations greater than 10% produced moderate to strong irritation of the skin. [5]

Occupational exposure

The CDC has reported on occupations which were routinely exposed to ALS between 1981 and 1983. During this time, the occupation with the highest number of workers exposed was registered nurses, followed closely by funeral directors. [6]

Environment

The HERA project also conducted an environmental review of alkyl sulfates that found all alkyl sulfates are readily biodegradable and standard wastewater treatment operations removed 96–99.96% of short-chain (12–14 carbons) alkyl sulfates. Even in anaerobic conditions at least 80% of the original volume is biodegraded after 15 days with 90% degradation after 4 weeks. [7]

See also

Related Research Articles

Sodium laureth sulfate (SLES), an accepted contraction of sodium lauryl ether sulfate (SLES), also called sodium alkylethersulfate, is an anionic detergent and surfactant found in many personal care products and for industrial uses. SLES is an inexpensive and very effective foaming agent. SLES, sodium lauryl sulfate (SLS), ammonium lauryl sulfate (ALS), and sodium pareth sulfate are surfactants that are used in many cosmetic products for their cleaning and emulsifying properties. It is derived from palm kernel oil or coconut oil. In herbicides, it is used as a surfactant to improve absorption of the herbicidal chemicals and reduces time the product takes to be rainfast, when enough of the herbicidal agent will be absorbed.

Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula CH3(CH2)11OSO3Na and structure H3C(CH2)11−O−S(=O)2−ONa+. It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium salt of the 12-carbon organosulfate. Its hydrocarbon tail combined with a polar "headgroup" give the compound amphiphilic properties that make it useful as a detergent. SDS is also component of mixtures produced from inexpensive coconut and palm oils. SDS is a common component of many domestic cleaning, personal hygiene and cosmetic, pharmaceutical, and food products, as well as of industrial and commercial cleaning and product formulations.

<span class="mw-page-title-main">Detergent</span> Surfactants with cleansing properties

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 more soluble in hard water, because the polar sulfonate is less likely than the polar carboxylate to bind to calcium and other ions found in hard water.

<span class="mw-page-title-main">Surfactant</span> Substance that lowers the surface tension between a liquid and another material

Surfactants are chemical compounds that decrease the surface tension or interfacial tension between two liquids, a liquid and a gas, or a liquid and a solid. The word "surfactant" is a blend of surface-active agent, coined c. 1950. As they consist of a water-repellent and a water-attracting part, they enable water and oil to mix; they can form foam and facilitate the detachment of dirt.

In organic chemistry, ethoxylation is a chemical reaction in which ethylene oxide adds to a substrate. It is the most widely practiced alkoxylation, which involves the addition of epoxides to substrates.

<span class="mw-page-title-main">Quaternary ammonium cation</span> Polyatomic ions of the form N(–R)₄ (charge +1)

In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure [NR4]+, where R is an alkyl group, an aryl group or organyl group. Unlike the ammonium ion and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule.

Fatty alcohols (or long-chain alcohols) are usually high-molecular-weight, straight-chain primary alcohols, but can also range from as few as 4–6 carbons to as many as 22–26, derived from natural fats and oils. The precise chain length varies with the source. Some commercially important fatty alcohols are lauryl, stearyl, and oleyl alcohols. They are colourless oily liquids (for smaller carbon numbers) or waxy solids, although impure samples may appear yellow. Fatty alcohols usually have an even number of carbon atoms and a single alcohol group (–OH) attached to the terminal carbon. Some are unsaturated and some are branched. They are widely used in industry. As with fatty acids, they are often referred to generically by the number of carbon atoms in the molecule, such as "a C12 alcohol", that is an alcohol having 12 carbons, for example dodecanol.

Dodecanol, or lauryl alcohol, is an organic compound produced industrially from palm kernel oil or coconut oil. It is a fatty alcohol. Sulfate esters of lauryl alcohol, especially sodium lauryl sulfate, are very widely used as surfactants. Sodium lauryl sulfate and the related dodecanol derivatives ammonium lauryl sulfate and sodium laureth sulfate are all used in shampoos. Dodecanol is tasteless, colorless, and has a floral odor.

A foaming agent is a material such as a surfactant or a blowing agent that facilitates the formation of foam. A surfactant, when present in small amounts, reduces surface tension of a liquid or increases its colloidal stability by inhibiting coalescence of bubbles. A blowing agent is a gas that forms the gaseous part of the foam.

Sodium myreth sulfate is a mixture of organic compounds with both detergent and surfactant properties. It is found in many personal care products such as soaps, shampoos, and toothpaste. It is an inexpensive and effective foaming agent. Typical of many detergents, sodium myreth sulfate consists of several closely related compounds. Sometimes the number of ethylene glycol ether units (n) is specified in the name as myreth-n sulfate, for example myreth-2 sulfate.

<span class="mw-page-title-main">Amphiphile</span> Hydrophilic and lipophilic chemical compound

An amphiphile, or amphipath, is a chemical compound possessing both hydrophilic and lipophilic (fat-loving) properties. Such a compound is called amphiphilic or amphipathic. Amphiphilic compounds include surfactants and detergents. The phospholipid amphiphiles are the major structural component of cell membranes.

<span class="mw-page-title-main">Amine oxide</span> Chemical compound containing the functional group R3N→O

In chemistry, an amine oxide, also known as an amine N-oxide or simply N-oxide, is a chemical compound that has the chemical formula R3N+−O. It contains a nitrogen-oxygen coordinate covalent bond with three additional hydrogen and/or substituent-groups attached to nitrogen. Sometimes it is written as R3N→O or, alternatively, as R3N=O.

<span class="mw-page-title-main">Cetrimonium bromide</span> Quaternary ammonium surfactant and antiseptic agent

Cetrimonium bromide, also known with the abbreviation CTAB, is a quaternary ammonium surfactant with a condensed structural formula [(C16H33)N(CH3)3]Br.

<span class="mw-page-title-main">Baby shampoo</span> Personal care product

Baby shampoo is a hair care product that is used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair; specially formulated for use on infants and young children by means of substituting chemicals which are purportedly less irritating to the eyes than those commonly found in regular shampoo.

<span class="mw-page-title-main">Organosulfate</span> Organic compounds of the form R–O–SO₃ (charge –1)

In organosulfur chemistry, organosulfates are a class of organic compounds sharing a common functional group with the structure R−O−SO−3. The SO4 core is a sulfate group and the R group is any organic residue. All organosulfates are formally esters derived from alcohols and sulfuric acid although many are not prepared in this way. Many sulfate esters are used in detergents, and some are useful reagents. Alkyl sulfates consist of a hydrophobic hydrocarbon chain, a polar sulfate group and either a cation or amine to neutralize the sulfate group. Examples include: sodium lauryl sulfate and related potassium and ammonium salts.

A hydrotrope is a compound that solubilizes hydrophobic compounds in aqueous solutions by means other than micellar solubilization. Typically, hydrotropes consist of a hydrophilic part and a hydrophobic part, but the hydrophobic part is generally too small to cause spontaneous self-aggregation. Hydrotropes do not have a critical concentration above which self-aggregation spontaneously starts to occur. Instead, some hydrotropes aggregate in a step-wise self-aggregation process, gradually increasing aggregation size. However, many hydrotropes do not seem to self-aggregate at all, unless a solubilizate has been added. Examples of hydrotropes include urea, tosylate, cumenesulfonate and xylenesulfonate.

<span class="mw-page-title-main">Shampoo</span> Hair care product

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 scalp, and then rinsing it out. Some users may follow a shampooing with the use of hair conditioner.

A soap substitute is a natural or synthetic cleaning product used in place of soap or other detergents, typically to reduce environmental impact or health harms or provide other benefits.

Hair washing without commercial shampoo, sometimes called no poo, includes water-only hair washing or hair washing with non-commercial products, such as baking soda and vinegar. Advocates argue that commercial shampoo is an unnecessary expense and may contain harmful ingredients.

α-Olefin sulfonate Class of chemical compounds

α-Olefin sulfonates are a group of anionic surfactants, which are used as detergents. The compounds contain a - mostly linear, primary - alkyl R and a monovalent cation M, preferably sodium. The most frequently used example of this group of substances is sodium α-olefin sulfonate.

References

  1. Ammonium lauryl sulfate in the Consumer Product Information Database
  2. 1 2 Kosswig, Kurt (2000). "Surfactants". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a25_747. ISBN   978-3527306732.
  3. "Chemical Information Sheet – Ammonium Lauryl Sulfate" (PDF). Archived from the original (PDF) on 2006-08-23. Retrieved 2007-01-25.
  4. "Final Report on the Safety Assessment of Sodium Lauryl Sulfate and Ammonium Lauryl Sulfate". JACT, CIR Publication. 2 (7): 127–81. 1983.
  5. "Human and Environmental Risk Assessment – Health Risks of Alkyl Sulfates" (PDF). Retrieved 2007-01-25.
  6. "National Exposure Survey (1981–1983)". Archived from the original on 2006-03-27. Retrieved 2007-01-25.
  7. "Human and Environmental Risk Assessment for Alkyl Sulphates" (PDF). Archived from the original (PDF) on 2006-11-07. Retrieved 2007-01-25.