67-461: 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 (of detergents) is less likely than the polar carboxylate (of soap) to bind to calcium and other ions found in hard water. The word detergent
134-399: A hydrocarbon chain, which can be branched, linear, or aromatic. Fluorosurfactants have fluorocarbon chains. Siloxane surfactants have siloxane chains. Many important surfactants include a polyether chain terminating in a highly polar anionic group. The polyether groups often comprise ethoxylated ( polyethylene oxide -like) sequences inserted to increase the hydrophilic character of
201-437: A hydrophilic "water-seeking" group (the head ), and a hydrophobic "water-avoiding" group (the tail ). As a result, a surfactant contains both a water-soluble component and a water-insoluble component. Surfactants diffuse in water and get adsorbed at interfaces between air and water, or at the interface between oil and water in the case where water is mixed with oil. The water-insoluble hydrophobic group may extend out of
268-774: A "universal detergent" ( Universalwaschmittel ) in Germany. Soda was then mixed with sodium silicate to produce Germany's first brand name detergent Bleichsoda. In 1907, Henkel also added a bleaching agent sodium perborate to launch the first 'self-acting' laundry detergent Persil to eliminate the laborious rubbing of laundry by hand. During the First World War , there was a shortage of oils and fats needed to make soap. In order to find alternatives for soap, synthetic detergents were made in Germany by chemists using raw material derived from coal tar. These early products, however, did not provide sufficient detergency. In 1928, effective detergent
335-401: A PEG structure to another larger molecule, for example, a therapeutic protein , which is then referred to as a PEGylated protein. PEGylated interferon alfa-2a or alfa-2b are commonly used injectable treatments for hepatitis C infection. PEG is soluble in water , methanol , ethanol , acetonitrile , benzene , and dichloromethane , and is insoluble in diethyl ether and hexane . It
402-471: A detergent in the true sense. In domestic contexts, the term detergent refers to household cleaning products such as laundry detergent or dish detergent , which are in fact complex mixtures of different compounds, not all of which are by themselves detergents. Detergency is the ability to remove unwanted substances termed 'soils' from a substrate (e.g., clothing). Detergents are a group of compounds with an amphiphilic structure, where each molecule has
469-407: A distribution of molecular weights (i.e. they are polydisperse). The size distribution can be characterized statistically by its weight average molecular weight ( M w ) and its number average molecular weight ( M n ), the ratio of which is called the polydispersity index ( Đ M ). M w and M n can be measured by mass spectrometry . PEGylation is the act of covalently coupling
536-449: A hydrophilic (polar) head and a long hydrophobic (non-polar) tail. The hydrophobic portion of these molecules may be straight- or branched-chain hydrocarbons , or it may have a steroid structure. The hydrophilic portion is more varied, they may be ionic or non-ionic, and can range from a simple or a relatively elaborate structure. Detergents are surfactants since they can decrease the surface tension of water. Their dual nature facilitates
603-606: A net positive, or negative, charge. If the charge is negative, the surfactant is more specifically called anionic ; if the charge is positive, it is called cationic . If a surfactant contains a head with two oppositely charged groups, it is termed zwitterionic , or amphoteric . Commonly encountered surfactants of each type include: Anionic surfactants contain anionic functional groups at their head, such as sulfate , sulfonate , phosphate , and carboxylates . Prominent alkyl sulfates include ammonium lauryl sulfate , sodium lauryl sulfate (sodium dodecyl sulfate, SLS, or SDS), and
670-476: A phosphate anion with an amine or ammonium, such as the phospholipids phosphatidylserine , phosphatidylethanolamine , phosphatidylcholine , and sphingomyelins . Lauryldimethylamine oxide and myristamine oxide are two commonly used zwitterionic surfactants of the tertiary amine oxides structural type. Non-ionic surfactants have covalently bonded oxygen-containing hydrophilic groups, which are bonded to hydrophobic parent structures. The water-solubility of
737-427: A sugar as their uncharged hydrophilic headgroup. Examples include octyl thioglucoside and maltosides . HEGA and MEGA series detergents are similar, possessing a sugar alcohol as headgroup. Amphoteric or zwitterionic detergents have zwitterions within a particular pH range, and possess a net zero charge arising from the presence of equal numbers of +1 and −1 charged chemical groups. Examples include CHAPS . Soap
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#1733086228024804-413: A surfactant produced in the liver, play an important role in digestion. Most anionic and non-ionic surfactants are non-toxic, having LD50 comparable to table salt . The toxicity of quaternary ammonium compounds , which are antibacterial and antifungal , varies. Dialkyldimethylammonium chlorides ( DDAC , DSDMAC ) used as fabric softeners have high LD50 (5 g/kg) and are essentially non-toxic, while
871-400: A surfactant. Polypropylene oxides conversely, may be inserted to increase the lipophilic character of a surfactant. Surfactant molecules have either one tail or two; those with two tails are said to be double-chained . Most commonly, surfactants are classified according to polar head group. A non-ionic surfactant has no charged groups in its head. The head of an ionic surfactant carries
938-647: A variety of chemical species by dissociating aggregates and unfolding proteins. Popular surfactants in the biochemistry laboratory are sodium lauryl sulfate (SDS) and cetyl trimethylammonium bromide (CTAB). Detergents are key reagents to extract protein by lysis of the cells and tissues: They disorganize the membrane's lipid bilayer (SDS, Triton X-100 , X-114 , CHAPS , DOC , and NP-40 ), and solubilize proteins. Milder detergents such as octyl thioglucoside , octyl glucoside or dodecyl maltoside are used to solubilize membrane proteins such as enzymes and receptors without denaturing them. Non-solubilized material
1005-450: A wide range of molecular weights from 300 g/mol to 10,000,000 g/mol. PEG and PEO are liquids or low-melting solids, depending on their molecular weights . While PEG and PEO with different molecular weights find use in different applications and have different physical properties (e.g. viscosity ) due to chain length effects, their chemical properties are nearly identical. Different forms of PEG are also available, depending on
1072-492: Is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine . PEG is also known as polyethylene oxide ( PEO ) or polyoxyethylene ( POE ), depending on its molecular weight . The structure of PEG is commonly expressed as H−(O−CH 2 −CH 2 ) n −OH. PEO's have "very low single dose oral toxicity", on the order of tens of grams per kilogram of human body weight when ingested by mouth. Because of its low toxicity, PEO
1139-412: Is coupled to hydrophobic molecules to produce non-ionic surfactants . PEG and related polymers (PEG phospholipid constructs) are often sonicated when used in biomedical applications. However, as reported by Murali et al., PEG is very sensitive to sonolytic degradation and PEG degradation products can be toxic to mammalian cells. It is, thus, imperative to assess potential PEG degradation to ensure that
1206-449: Is derived from the Latin adjective detergens , from the verb detergere , meaning to wipe or polish off. Detergent can be defined as a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions . However, conventionally, detergent is used to mean synthetic cleaning compounds as opposed to soap (a salt of the natural fatty acid ), even though soap is also
1273-413: Is difficult, the price for this type of quality is often 10–1000 fold that of polydisperse PEG. PEGs are also available with different geometries. The numbers that are often included in the names of PEGs indicate their average molecular weights (e.g. a PEG with n = 9 would have an average molecular weight of approximately 400 daltons , and would be labeled PEG 400 ). Most PEGs include molecules with
1340-412: Is estimated at 15 million tons per year, of which about half are soaps . Other surfactants produced on a particularly large scale are linear alkylbenzene sulfonates (1.7 million tons/y), lignin sulfonates (600,000 tons/y), fatty alcohol ethoxylates (700,000 tons/y), and alkylphenol ethoxylates (500,000 tons/y). In the bulk aqueous phase, surfactants form aggregates, such as micelles , where
1407-414: Is harvested by centrifugation or other means. For electrophoresis , for example, proteins are classically treated with SDS to denature the native tertiary and quaternary structures , allowing the separation of proteins according to their molecular weight . Detergents have also been used to decellularise organs. This process maintains a matrix of proteins that preserves the structure of the organ and often
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#17330862280241474-549: Is known to have been used as a surfactant for washing clothes since the Sumerian time in 2,500 B.C. In ancient Egypt , soda was used as a wash additive. In the 19th century, synthetic surfactants began to be created, for example from olive oil. Sodium silicate (water glass) was used in soap-making in the United States in the 1860s, and in 1876, Henkel sold a sodium silicate-based product that can be used with soap and marketed as
1541-430: Is ongoing in how surfactants arrange themselves on the surface of the quantum dots. Surfactants play an important role in droplet-based microfluidics in the stabilization of the droplets, and the prevention of the fusion of droplets during incubation. Janus-type material is used as a surfactant-like heterogeneous catalyst for the synthesis of adipic acid. Agents that increase surface tension are "surface active" in
1608-476: Is positively charged. Cationic surfactants generally have poor detergency. Non-ionic detergents are characterized by their uncharged, hydrophilic headgroups. Typical non-ionic detergents are based on polyoxyethylene or a glycoside . Common examples of the former include Tween , Triton , and the Brij series. These materials are also known as ethoxylates or PEGylates and their metabolites, nonylphenol . Glycosides have
1675-485: Is preferred in the biomedical field, whereas PEO is more prevalent in the field of polymer chemistry. Because different applications require different polymer chain lengths, PEG has tended to refer to oligomers and polymers with a molecular mass below 20,000 g/mol, PEO to polymers with a molecular mass above 20,000 g/mol, and POE to a polymer of any molecular mass. PEGs are prepared by polymerization of ethylene oxide and are commercially available over
1742-401: Is produced by the interaction of ethylene oxide with water, ethylene glycol , or ethylene glycol oligomers. The reaction is catalyzed by acidic or basic catalysts. Ethylene glycol and its oligomers are preferable as a starting material instead of water because they allow the creation of polymers with a low polydispersity (narrow molecular weight distribution). Polymer chain length depends on
1809-457: Is produced in the lungs in order to facilitate breathing by increasing total lung capacity , and lung compliance . In respiratory distress syndrome or RDS, surfactant replacement therapy helps patients have normal respiration by using pharmaceutical forms of the surfactants. One example of a pharmaceutical pulmonary surfactant is Survanta ( beractant ) or its generic form Beraksurf, produced by Abbvie and Tekzima respectively. Bile salts ,
1876-399: Is the critical micelle concentration (CMC), and the temperature at which the micelles further aggregate to separate the solution into two phases is the cloud point when the solution becomes cloudy and detergency is optimal. Detergents work better in an alkaline pH. The properties of detergents are dependent on the molecular structure of the monomer . The ability to foam may be determined by
1943-541: Is the hydrophilic-lipophilic balance (HLB). Surfactants reduce the surface tension of water by adsorbing at the liquid-air interface. The relation that links the surface tension and the surface excess is known as the Gibbs isotherm . The dynamics of surfactant adsorption is of great importance for practical applications such as in foaming, emulsifying or coating processes, where bubbles or drops are rapidly generated and need to be stabilized. The dynamics of absorption depend on
2010-636: Is thought to be an endocrine disruptor . Interest in biodegradable surfactants has led to much interest in "biosurfactants" such as those derived from amino acids. Biobased surfactants can offer improved biodegradation. However, whether surfactants damage the cells of fish or cause foam mountains on bodies of water depends primarily on their chemical structure and not on whether the carbon originally used came from fossil sources, carbon dioxide or biomass. Polyoxyethylene Polyethylene glycol ( PEG ; / ˌ p ɒ l i ˈ ɛ θ əl ˌ iː n ˈ ɡ l aɪ ˌ k ɒ l , - ˈ ɛ θ ɪ l -, - ˌ k ɔː l / )
2077-476: Is used in a variety of edible products. It is also used as a lubricating coating for various surfaces in aqueous and non-aqueous applications. The precursor to PEGs is ethylene oxide , which is hazardous. Ethylene glycol and its ethers are nephrotoxic ( poisonous to the kidneys ) if applied to damaged skin. The United States Food and Drug Administration (FDA or US FDA) regards PEG as biologically inert and safe. A 2015 study appears to challenge
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2144-480: The diffusion coefficient of the surfactant. As the interface is created, the adsorption is limited by the diffusion of the surfactant to the interface. In some cases, there can exist an energetic barrier to adsorption or desorption of the surfactant. If such a barrier limits the adsorption rate, the dynamics are said to be ‘kinetically limited'. Such energy barriers can be due to steric or electrostatic repulsions . The surface rheology of surfactant layers, including
2211-551: The disinfectant alkylbenzyldimethylammonium chloride has an LD50 of 0.35 g/kg. Prolonged exposure to surfactants can irritate and damage the skin because surfactants disrupt the lipid membrane that protects skin and other cells. Skin irritancy generally increases in the series non-ionic, amphoteric, anionic, cationic surfactants. Surfactants are routinely deposited in numerous ways on land and into water systems, whether as part of an intended process or as industrial and household waste. Anionic surfactants can be found in soils as
2278-481: The initiator used for the polymerization process – the most common initiator is a monofunctional methyl ether PEG, or methoxypoly(ethylene glycol), abbreviated mPEG. Lower-molecular-weight PEGs are also available as purer oligomers, referred to as monodisperse, uniform, or discrete. Very high-purity PEG has recently been shown to be crystalline, allowing the determination of a crystal structure by x-ray crystallography . Since purification and separation of pure oligomers
2345-810: 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 surf ace- act ive a ge nt , coined in 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. Surfactants are among the most widespread and commercially important chemicals. Private households as well as many industries use them in large quantities as detergents and cleaning agents , but also for example as emulsifiers , wetting agents, foaming agents , antistatic additives, or dispersants . Surfactants occur naturally in traditional plant-based detergents, e.g. horse chestnuts or soap nuts ; they can also be found in
2412-459: The FDA's conclusion. In the study, a high-sensitivity ELISA assay detected anti-PEG antibodies in 72% of random blood plasma samples collected from 1990 to 1999. According to the study's authors, this result suggests that anti-PEG antibodies may be present, typically at low levels, in people who were never treated with PEGylated drugs. Due to its ubiquity in many products and the large percentage of
2479-531: The United States, detergents were sold in 1933 by Procter & Gamble ( Dreft ) primarily in areas with hard water. However, sales in the US grew slowly until the introduction of 'built' detergents with the addition of effective phosphate builder developed in the early 1940s. The builder improves the performance of the surfactants by softening the water through the chelation of calcium and magnesium ions, helping to maintain an alkaline pH, as well as dispersing and keeping
2546-459: The application and the highly competitive consumer market. These detergents may contain the following components: Both carburetors and fuel injector components of internal combustion engines benefit from detergents in the fuels to prevent fouling . Concentrations are about 300 ppm . Typical detergents are long-chain amines and amides such as polyisobuteneamine and polyisobuteneamide/ succinimide . Reagent grade detergents are employed for
2613-480: The bulk water phase into a non-water phase such as air or oil phase, while the water-soluble head group remains bound in the water phase. The hydrophobic tail may be either lipophilic ("oil-seeking") or lipophobic ("oil-avoiding") depending on its chemistry. Hydrocarbon groups are usually lipophilic, for use in soaps and detergents, while fluorocarbon groups are lipophobic, for use in repelling stains or reducing surface tension. World production of surfactants
2680-630: The choice is primarily governed having regard to the costs of special properties (e.g., effectiveness and efficiency, toxicity, dermatological compatibility, biodegradability ) or permission for use in food. Fatty acid ethoxylates are a class of very versatile surfactants, which combine in a single molecule the characteristic of a weakly anionic, pH-responsive head group with the presence of stabilizing and temperature responsive ethyleneoxide units. Spans : Tweens : Surfactants are usually organic compounds that are akin to amphiphilic , which means that this molecule, being as double-agent, each contains
2747-472: The displacement of air from the matrix of cotton pads and bandages so that medicinal solutions can be absorbed for application to various body areas. They also act to displace dirt and debris by the use of detergents in the washing of wounds and via the application of medicinal lotions and sprays to surface of skin and mucous membranes. Surfactants enhance remediation via soil washing, bioremediation, and phytoremediation. In solution, detergents help solubilize
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2814-497: The elasticity and viscosity of the layer, play an important role in the stability of foams and emulsions. Interfacial and surface tension can be characterized by classical methods such as the -pendant or spinning drop method . Dynamic surface tensions, i.e. surface tension as a function of time, can be obtained by the maximum bubble pressure apparatus The structure of surfactant layers can be studied by ellipsometry or X-ray reflectivity . Surface rheology can be characterized by
2881-535: The environment, for example laundry detergents in waters, their biodegradation is of great interest. Attracting much attention is the non-biodegradability and extreme persistence of fluorosurfactant , e.g. perfluorooctanoic acid (PFOA). Strategies to enhance degradation include ozone treatment and biodegradation. Two major surfactants, linear alkylbenzene sulfonates (LAS) and the alkyl phenol ethoxylates (APE) break down under aerobic conditions found in sewage treatment plants and in soil to nonylphenol , which
2948-409: The environment, which led to their replacement by surfactants that are more biodegradable, such as linear alkylbenzene sulfonate. Developments over the years have included the use of enzymes , substitutes for phosphates such as zeolite A and NTA , TAED as bleach activator , sugar-based surfactants which are biodegradable and milder to skin, and other green friendly products, as well as changes to
3015-416: The final material does not contain undocumented contaminants that can introduce artifacts into experimental results. PEGs and methoxypolyethylene glycols are manufactured by Dow Chemical under the trade name Carbowax for industrial use, and Carbowax Sentry for food and pharmaceutical use. They vary in consistency from liquid to solid, depending on the molecular weight, as indicated by a number following
3082-415: The form of delivery such as tablets, gels and pods . One of the largest applications of detergents is for household and shop cleaning including dish washing and washing laundry . These detergents are commonly available as powders or concentrated solutions, and the formulations of these detergents are often complex mixtures of a variety of chemicals aside from surfactants, reflecting the diverse demands of
3149-428: The formation of sludge or deposits. The formulation of detergent products may include bleach , fragrances, dyes and other additives. The use of phosphates in detergent , however, led to concerns over nutrient pollution and demand for changes to the formulation of the detergents. Concerns were also raised over the use of surfactants such as branched alkylbenzene sulfonate (tetrapropylenebenzene sulfonate) that lingers in
3216-632: The head group, for example anionic surfactants are high-foaming, while nonionic surfactants may be non-foaming or low-foaming. Detergents are classified into four broad groupings, depending on the electrical charge of the surfactants. Typical anionic detergents are alkylbenzene sulfonates . The alkylbenzene portion of these anions is lipophilic and the sulfonate is hydrophilic. Two varieties have been popularized, those with branched alkyl groups and those with linear alkyl groups. The former were largely phased out in economically advanced societies because they are poorly biodegradable. Anionic detergents are
3283-409: The hydrophobic tails form the core of the aggregate and the hydrophilic heads are in contact with the surrounding liquid. Other types of aggregates can also be formed, such as spherical or cylindrical micelles or lipid bilayers . The shape of the aggregates depends on the chemical structure of the surfactants, namely the balance in size between the hydrophilic head and hydrophobic tail. A measure of this
3350-573: The isolation and purification of integral membrane proteins found in biological cells . Solubilization of cell membrane bilayers requires a detergent that can enter the inner membrane monolayer . Advancements in the purity and sophistication of detergents have facilitated structural and biophysical characterization of important membrane proteins such as ion channels also the disrupt membrane by binding lipopolysaccharide , transporters , signaling receptors , and photosystem II . Surfactant Surfactants are chemical compounds that decrease
3417-469: The literal sense but are not called surfactants as their effect is opposite to the common meaning. A common example of surface tension increase is salting out : adding an inorganic salt to an aqueous solution of a weakly polar substance will cause the substance to precipitate. The substance may itself be a surfactant, which is one of the reasons why many surfactants are ineffective in sea water. The human body produces diverse surfactants. Pulmonary surfactant
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#17330862280243484-422: The microvascular network. The process has been successfully used to prepare organs such as the liver and heart for transplant in rats. Pulmonary surfactants are also naturally secreted by type II cells of the lung alveoli in mammals . Surfactants are used with quantum dots in order to manipulate their growth, assembly, and electrical properties, in addition to mediating reactions on their surfaces. Research
3551-504: The mixture of hydrophobic compounds (like oil and grease) with water. Because air is not hydrophilic, detergents are also foaming agents to varying degrees. Detergent molecules aggregate to form micelles , which makes them soluble in water. The hydrophobic group of the detergent is the main driving force of micelle formation, its aggregation forms the hydrophobic core of the micelles. The micelle can remove grease, protein or soiling particles. The concentration at which micelles start to form
3618-445: The most common form of detergents, and an estimated 6 billion kilograms of anionic detergents are produced annually for the domestic markets. Bile acids , such as deoxycholic acid (DOC), are anionic detergents produced by the liver to aid in digestion and absorption of fats and oils. Cationic detergents are similar to anionic ones, but quaternary ammonium replaces the hydrophilic anionic sulfonate group. The ammonium sulfate center
3685-521: The name. They are used commercially in numerous applications, including foods, cosmetics , pharmaceutics, biomedicine , dispersing agents, solvents, ointments , suppository bases, as tablet excipients , and as laxatives . Some specific groups are lauromacrogols , nonoxynols , octoxynols , and poloxamers . The production of polyethylene glycol was first reported in 1859. Both A. V. Lourenço and Charles Adolphe Wurtz independently isolated products that were polyethylene glycols. Polyethylene glycol
3752-465: The ocean at the leak and on the sea-water's surface. The apparent theory was that the surfactants isolate droplets of oil, making it easier for petroleum-consuming microbes to digest the oil. The active ingredient in Corexit is dioctyl sodium sulfosuccinate (DOSS), sorbitan monooleate (Span 80), and polyoxyethylenated sorbitan monooleate ( Tween-80 ). Because of the volume of surfactants released into
3819-1048: The oscillating drop method or shear surface rheometers such as double-cone, double-ring or magnetic rod shear surface rheometer. Surfactants play an important role as cleaning, wetting , dispersing , emulsifying , foaming and anti-foaming agents in many practical applications and products, including detergents , fabric softeners , motor oils , emulsions , soaps , paints , adhesives , inks , anti-fogs , ski waxes , snowboard wax, deinking of recycled papers , in flotation, washing and enzymatic processes, and laxatives . Also agrochemical formulations such as herbicides (some), insecticides , biocides (sanitizers), and spermicides ( nonoxynol-9 ). Personal care products such as cosmetics , shampoos , shower gel , hair conditioners , and toothpastes . Surfactants are used in firefighting (to make "wet water" that more quickly soaks into flammable materials ) and pipelines (liquid drag reducing agents). Alkali surfactant polymers are used to mobilize oil in oil wells . Surfactants act to cause
3886-411: The oxygen groups is the result of hydrogen bonding . Hydrogen bonding decreases with increasing temperature, and the water solubility of non-ionic surfactants therefore decreases with increasing temperature. Non-ionic surfactants are less sensitive to water hardness than anionic surfactants, and they foam less strongly. The differences between the individual types of non-ionic surfactants are slight, and
3953-530: The population with antibodies to PEG, which indicates an allergic reaction, hypersensitive reactions to PEG are an increasing health concern. Allergy to PEG is usually discovered after a person has been diagnosed with an allergy to several seemingly unrelated products—including processed foods, cosmetics, drugs, and other substances—that contain or were manufactured with PEG. PEG , PEO , and POE refer to an oligomer or polymer of ethylene oxide . The three names are chemically synonymous, but historically PEG
4020-488: The ratio of reactants. Depending on the catalyst type, the mechanism of polymerization can be cationic or anionic. The anionic mechanism is preferable because it allows one to obtain PEG with a low polydispersity . Polymerization of ethylene oxide is an exothermic process. Overheating or contaminating ethylene oxide with catalysts such as alkalis or metal oxides can lead to runaway polymerization, which can end in an explosion after
4087-951: The related alkyl-ether sulfates sodium laureth sulfate (sodium lauryl ether sulfate or SLES), and sodium myreth sulfate . Others include: Carboxylates are the most common surfactants and comprise the carboxylate salts (soaps), such as sodium stearate . More specialized species include sodium lauroyl sarcosinate and carboxylate-based fluorosurfactants such as perfluorononanoate , perfluorooctanoate (PFOA or PFO). pH-dependent primary, secondary, or tertiary amines ; primary and secondary amines become positively charged at pH < 10: octenidine dihydrochloride . Permanently charged quaternary ammonium salts : cetrimonium bromide (CTAB), cetylpyridinium chloride (CPC), benzalkonium chloride (BAC), benzethonium chloride (BZT), dimethyldioctadecylammonium chloride , and dioctadecyldimethylammonium bromide (DODAB). Zwitterionic ( ampholytic ) surfactants have both cationic and anionic centers attached to
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#17330862280244154-488: The result of sewage sludge application, wastewater irrigation, and remediation processes. Relatively high concentrations of surfactants together with multimetals can represent an environmental risk. At low concentrations, surfactant application is unlikely to have a significant effect on trace metal mobility. In the case of the Deepwater Horizon oil spill , unprecedented amounts of Corexit were sprayed directly into
4221-452: The same molecule. The cationic part is based on primary, secondary, or tertiary amines or quaternary ammonium cations. The anionic part can be more variable and include sulfonates, as in the sultaines CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) and cocamidopropyl hydroxysultaine . Betaines such as cocamidopropyl betaine have a carboxylate with the ammonium. The most common biological zwitterionic surfactants have
4288-618: The secretions of some caterpillars. Today one of the most commonly used anionic surfactants, linear alkylbenzene sulfates (LAS), are produced from petroleum products . However, surfactants are increasingly produced in whole or in part from renewable biomass , like sugar, fatty alcohol from vegetable oils, by-products of biofuel production, or other biogenic material. Most surfactants are organic compounds with hydrophilic "heads" and hydrophobic "tails." The "heads" of surfactants are polar and may or may not carry an electrical charge. The "tails" of most surfactants are fairly similar, consisting of
4355-462: The soiling particles in solution. The development of the petrochemical industry after the Second World War also yielded material for the production of a range of synthetic surfactants, and alkylbenzene sulfonates became the most important detergent surfactants used. By the 1950s, laundry detergents had become widespread, and largely replaced soap for cleaning clothes in developed countries. Over
4422-471: The years, many types of detergents have been developed for a variety of purposes, for example, low-sudsing detergents for use in front-loading washing machines, heavy-duty detergents effective in removing grease and dirt, all-purpose detergents and specialty detergents. They become incorporated in various products outside of laundry use, for example in dishwasher detergents , shampoo, toothpaste, industrial cleaners, and in lubricants and fuels to reduce or prevent
4489-461: Was made through the sulfation of fatty alcohol , but large-scale production was not feasible until low-cost fatty alcohols become available in the early 1930s. The synthetic detergent created was more effective and less likely to form scum than soap in hard water, and can also eliminate acid and alkaline reactions and decompose dirt. Commercial detergent products with fatty alcohol sulphates began to be sold, initially in 1932 in Germany by Henkel . In
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