Detergent#Cationic detergents

{{wiktionary|detergent}}

The word detergent 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 a detergent in the true sense.{{cite book|author=NIIR Board of Consultants Engineers |title=The Complete Technology Book on Detergents |edition=2nd Revised|url={{Google Books |qgC_CwAAQBAJ|page=1|plain-url=yes}}|date=2013|isbn=9789381039199|page=1 |publisher=Niir Project Consultancy Services |via=Google Books}} 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).{{cite book|editor=Arno Cahn |title=5th World Conference on Detergents|url={{Google Books |VMqSJROG_WYC|page=154|plain-url=yes}}|date=2003|isbn=9781893997400|page=154 |publisher=The American Oil Chemists Society |via=Google Books}}

Detergents are a group of compounds with an amphiphilic structure, where each molecule has 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.{{cite book |title=Detergents: An overview |series=Methods in Enzymology |volume= 182|year= 1990|pages= 239–253 |first=Judith M. |last=Neugebauer |chapter=[18] Detergents: An overview |doi=10.1016/0076-6879(90)82020-3 |pmid=2314239 |isbn=9780121820831 }} Detergents are surfactants since they can decrease the surface tension of water. Their dual nature facilitates the mixture of hydrophobic compounds (like oil and grease) with water. Because air is not hydrophilic, detergents are also foaming agents to varying degrees.

File:Micelle scheme-en.svg

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 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 the head group, for example anionic surfactants are high-foaming, while nonionic surfactants may be non-foaming or low-foaming.{{cite book|author=Niir Board |title=Handbook on Soaps, Detergents & Acid Slurry|url={{Google Books |vvQvDAAAQBAJ|page=270|plain-url=yes}}|date=1999|isbn=9788178330938|page=270 |publisher=Asia Pacific Business Press |via=Google Books|edition=3rd Revised }}

Detergents are classified into four broad groupings, depending on the electrical charge of the surfactants.{{cite book|editor=Guy Broze |first=Ammanuel |last=Mehreteab |title=Handbook of Detergents, Part A|url={{Google Books |iwsVEAAAQBAJ|page=133|plain-url=yes}}|date=1999|isbn=9781439833322|pages=133–134 |publisher=Taylor & Francis|via=Google Books}}

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.Eduard Smulders, Wolfgang Rybinski, Eric Sung, Wilfried Rähse, Josef Steber, Frederike Wiebel, Anette Nordskog, "Laundry Detergents" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a08_315.pub2}}

Anionic detergents are 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.

File:Soap&Detergents.png, and a soap.]]

Cationic detergents are similar to anionic ones, but quaternary ammonium replaces the hydrophilic anionic sulfonate group. The ammonium sulfate center 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 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.

{{further|Surfactant#Applications and sources}}

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.

{{see also|Soap#History}}

Soap is known to have been used as a surfactant for washing clothes since the Sumerian time in 2,500 B.C.{{cite book|editor=Jürgen Falbe |title=Surfactants in Consumer Products|url={{Google Books |SjvtCAAAQBAJ|page=1|plain-url=yes}}|date=2012|publisher=Springer-Verlag|isbn=9783642715457|pages=1–2 |via=Google Books}} 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,{{cite book|first= Fred |last= Aftalion|title=A History of the International Chemical Industry|url={{Google Books |zTP1MFJw8CsC|page=82|plain-url=yes}}|date=2001|publisher=Chemical Heritage Press|isbn=9780941901291|page=82}} and in 1876, Henkel sold a sodium silicate-based product that can be used with soap and marketed as a "universal detergent" (Universalwaschmittel) in Germany. Soda was then mixed with sodium silicate to produce Germany's first brand name detergent Bleichsoda.{{cite book|first1=James |last1=Ward |date= 2020|last2= Löhr|title=The Perfection of the Paper Clip|url={{Google Books |q6_YDwAAQBAJ|page=190|plain-url=yes}}|publisher=Atria Books|isbn=9781476799872|page=190}} 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.{{cite book|first1=Günter|last1= Jakobi |first2=Albrecht|last2= Löhr|title=Detergents and Textile Washing|url={{Google Books |is1TAAAAMAAJ|page=1|plain-url=yes}}|date=2012|publisher=Springer-Verlag|isbn=9780895736864|pages=3–4}}

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.{{cite web|url=http://www.cleaninginstitute.org/clean_living/soaps__detergent_history_3.aspx|title=Soaps & Detergent: History (1900s to Now)|publisher=American Cleaning Institute}} Retrieved on 6 January 2015{{cite book|author1=David O. Whitten|author2=Bessie Emrick Whitten|title=Handbook of American Business History: Extractives, manufacturing, and services|url={{Google Books |S-8god7-MlEC|page=221|plain-url=yes}}|date=1 January 1997|publisher=Greenwood Publishing Group|isbn=978-0-313-25199-3|pages=221–222 |via=Google Books}}{{cite book |url={{Google Books |dXn3aB1DKk4C|page=5|plain-url=yes}}|page=5 |title=Handbook of Detergents, Part F |editor =Paul Sosis, Uri Zoller |date= 2008 |publisher=CRC Press |isbn=9781420014655}} These early products, however, did not provide sufficient detergency. In 1928, effective detergent 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 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 the soiling particles in solution.{{cite book |url={{Google Books |hctgblTQD-sC|page=4|plain-url=yes}}|pages=4–5 |title=How to Formulate and Compound Industrial Detergents |first= David G. |last=Urban |date= 2003 |publisher=David G. Urban |isbn=9781588988683}} 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.{{cite book |url={{Google Books |dXn3aB1DKk4C|page=6|plain-url=yes}}|page=6 |title=Handbook of Detergents, Part F |editor =Paul Sosis, Uri Zoller |date= 2008 |publisher=CRC Press |isbn=9781420014655}} By the 1950s, laundry detergents had become widespread, and largely replaced soap for cleaning clothes in developed countries.{{cite book|editor=Jürgen Falbe |title=Surfactants in Consumer Products|url={{Google Books |SjvtCAAAQBAJ|page=4|plain-url=yes}}|date=2012|publisher=Springer-Verlag|isbn=9783642715457|pages=3–5 |via=Google Books}}

Over 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.{{cite book |url={{Google Books |dXn3aB1DKk4C|page=497|plain-url=yes}}|page=497 |title=Handbook of Detergents, Part F |editor =Paul Sosis, Uri Zoller |date= 2008 |isbn=9781420014655}} 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 the formation of sludge or deposits.{{cite book |url={{Google Books |mCgcrvvRIucC|page=331|plain-url=yes}}|page=331 |title=Handbook of Detergents, Part E: Applications |editor=Uri Zoller |date= 2008 |publisher=Taylor & Francis|isbn=9781574447576}} 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.{{cite book|author1=David O. Whitten|author2=Bessie Emrick Whitten|title=Handbook of Detergents, Part A|url={{Google Books |iwsVEAAAQBAJ|page=3|plain-url=yes}}|date=1999|publisher=Taylor & Francis|isbn=9781439833322|page=3 |via=Google Books}} Concerns were also raised over the use of surfactants such as branched alkylbenzene sulfonate (tetrapropylenebenzene sulfonate) that lingers in 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 the form of delivery such as tablets, gels and pods.{{cite book |url={{Google Books |VMqSJROG_WYC|page=64|plain-url=yes}}|pages=64–67 |title=5th World Conference on Detergents |editor=Arno Cahn|first=Birgit |last= Middelhauve|date= 2003 |publisher=The American Oil Chemists Society |isbn=9781893997400}}{{cite web |url= https://cleaning.lovetoknow.com/Laundry_Detergent_History |title=Laundry Detergent History|first= Heather |last=Long |work= Love to Know}}

File:Laundry detergent pods.jpgs]]

{{Main article|Laundry detergent|Dishwasher detergent}}

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 the application and the highly competitive consumer market. These detergents may contain the following components:

• surfactants
• foam regulators
• builders
• bleach
• bleach activators
• enzymes
• dyes
• fragrances
• other additives

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.Werner Dabelstein, Arno Reglitzky, Andrea Schütze, Klaus Reders "Automotive Fuels" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim{{doi|10.1002/14356007.a16_719.pub2}}

Reagent grade detergents are employed for the isolation and purification of integral membrane proteins found in biological cells.{{cite journal |vauthors=Koley D, Bard AJ | title=Triton X-100 concentration effects on membrane permeability of a single HeLa cell by scanning electrochemical microscopy (SECM) | journal= Proceedings of the National Academy of Sciences of the United States of America | volume=107 | issue=39 | year=2010 | pages=16783–7 | doi=10.1073/pnas.1011614107 | pmc=2947864 | pmid=20837548| bibcode=2010PNAS..10716783K | doi-access=free }} Solubilization of cell membrane bilayers requires a detergent that can enter the inner membrane monolayer.{{cite journal |vauthors=Lichtenberg D, Ahyayauch H, Goñi FM | title=The mechanism of detergent solubilization of lipid bilayers | journal= Biophysical Journal | volume=105 | issue=2 | year=2013 | pages=289–299 | doi=10.1016/j.bpj.2013.06.007 | pmc=3714928 | pmid=23870250| bibcode=2013BpJ...105..289L }} 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,{{cite journal | last1 = Doyle | first1 = DA | last2 = Morais Cabral | first2 = J | last3 = Pfuetzner | first3 = RA | last4 = Kuo | first4 = A | last5 = Gulbis | first5 = JM | last6 = Cohen | first6 = SL | last7 = Chait | first7 = BT | last8 = MacKinnon | first8 = R | year = 1998 | title = The structure of the potassium channel: molecular basis of K+conduction and selectivity | journal = Science | volume = 280 | issue = 5360| pages = 69–77 | doi=10.1126/science.280.5360.69 | pmid=9525859| bibcode = 1998Sci...280...69D }} transporters, signaling receptors, and photosystem II.{{cite journal | last1 = Umena | first1 = Yasufumi | last2 = Kawakami | first2 = Keisuke | last3 = Shen | first3 = Jian-Ren | last4 = Kamiya | first4 = Nobuo | year = 2011 | title = Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 A | url = http://ousar.lib.okayama-u.ac.jp/files/public/4/47455/20160528084139320094/Nature_473_55–60.pdf| journal = Nature | volume = 473 | issue = 7345| pages = 55–60 | doi = 10.1038/nature09913 | pmid=21499260| bibcode = 2011Natur.473...55U | s2cid = 205224374 }}

• Cleavable detergent
• Dishwashing liquid
• Dispersant
• Green cleaning
• Hard-surface cleaner
• Laundry detergent
• List of cleaning products
• Triton X-100

{{reflist}}

{{commons category|Detergents}}

• [http://chemistry.about.com/od/howthingswork/f/detergentfaq.htm About.com: How Do Detergents Clean] {{Webarchive|url=https://web.archive.org/web/20110106021626/http://chemistry.about.com/od/howthingswork/f/detergentfaq.htm |date=6 January 2011 }}
• [https://web.archive.org/web/20161119130839/http://www.chemistry.co.nz/deterginfo.htm Campbell tips] for detergents chemistry, [https://web.archive.org/web/20161129064828/http://www.chemistry.co.nz/surfactants.htm surfactants], and [https://web.archive.org/web/20161017172455/http://www.chemistry.co.nz/deterghistory.htm history] related to laundry washing, [https://web.archive.org/web/20161129092315/http://www.chemistry.co.nz/stain_frame.htm destaining methods] and [https://web.archive.org/web/20161018085331/http://www.chemistry.co.nz/soil_id.htm soil].
• [https://laundrydetergentideas.com/formulation-of-detergent/ Formulation of Detergent]

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Category:Cleaning products

Category:Membrane-active molecules

Category:Surfactants