What is the main purpose of surfactants?
Terms in this set (61)
- Preservatives
- Disinfectants (germicides)
- Modifying agents (A. Buffers, B. ...
- Anticoagulants- (water conditioners and water softeners)
- Surfactants (wetting agents, surface tension reducers, penetrating agents, surface active agents)
- Dyes (coloring agents- A. Cosmetic - Active B. ...
- Perfuming agents (masking agents)
- Vehicle. ...
What is surfactant and how does it affect of the lungs?
Surfactant reduces the surface tension of fluid in the lungs and helps make the small air sacs in the lungs (alveoli) more stable. This keeps them from collapsing when an individual exhales. In preparation for breathing air, fetuses begin making surfactant while still in the womb.
What are surfactants and how does it work?
surfactant, also called surface-active agent, substance such as a detergent that, when added to a liquid, reduces its surface tension, thereby increasing its spreading and wetting properties. In the dyeing of textiles, surfactants help the dye penetrate the fabric evenly.
What is the importance of surfactant in the body?
Pulmonary Surfactant
- Interfacial properties of therapeutic pulmonary surfactants studied by thin liquid films. Dotchi Exerowa, ...
- Interstitial Lung Disease. Mark P. ...
- Host susceptibility and resistance to Mycobacterium tuberculosis. ...
- The Surfactant System. ...
- Respiratory disorders. ...
- Respiratory Disorders in the Preterm Infant. ...
What is the purpose of a surfactant?
The main functions of surfactant are as follows: (1) lowering surface tension at the air–liquid interface and thus preventing alveolar collapse at end-expiration, (2) interacting with and subsequent killing of pathogens or preventing their dissemination, and (3) modulating immune responses.
Where are surfactants commonly used and for what purpose?
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, ...
Where are surfactants used?
Beyond soaps and detergents, surfactants are used in lubricants, inks, anti-fogging liquids, herbicides, adhesives, emulsifiers and fabric softeners. The human body even produces surfactants, known as pulmonary surfactants.
What 4 things can surfactants perform?
Here are ten things that surfactants can do in cosmetics.1 - Combine oil and water. One of the most useful things surfactants allow you to do in your formulations is to blend oils and water. ... 2 - Cleaning. ... 3 - Foaming. ... 4 - Conditioning. ... 5 - Spreading. ... 6 - Solubilizing. ... 7 - Opacifying. ... 8 - Thickening.More items...
What are the 4 types of surfactants?
Types of SurfactantsAnionic Surfactants. Anionic surfactants have a negative charge on their hydrophilic end. ... Nonionic Surfactants. Nonionic surfactants are neutral, they do not have any charge on their hydrophilic end. ... Cationic Surfactants. ... Amphoteric Surfactants.
What are examples of surfactants?
Sodium stearate is a good example of a surfactant. It is the most common surfactant in soap. Another common surfactant is 4-(5-dodecyl)benzenesulfonate. Other examples include docusate (dioctyl sodium sulfosuccinate), alkyl ether phosphates, benzalkaonium chloride (BAC), and perfluorooctanesulfonate (PFOS).
What is the best surfactant?
Anionic – Anionic surfactants are the most commonly used surfactants because they tend to provide the best cleaning power and the most foam. You've probably heard people talking about one of the most commonly used anionic surfactants, SLS (Sodium lauryl sulfate or Sodium Laureth Sulfate).
What is surfactant in soap?
Soaps and detergents are made from long molecules that contain a head and tail. These molecules are called surfactants; the diagram below represents a surfactant molecule. The head of the molecule is attracted to water (hydrophilic) and the tail is attracted to grease and dirt (hydrophobic).
Is washing soda a surfactant?
Bicarb or baking soda (sodium bicarbonate) is a pH adjuster. It isn't a water softener and it doesn't have any surfactant qualities.
What is surfactant in simple words?
surfactant, also called surface-active agent, substance such as a detergent that, when added to a liquid, reduces its surface tension, thereby increasing its spreading and wetting properties.
Are all detergents surfactants?
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.
What does surfactant do to water?
The surfactant reduces the surface tension of water by adsorbing at the liquid–gas interface. They also reduce the interfacial tension between oil and water by adsorbing at the liquid–liquid interface. CPE is the first extraction method in which a surfactant has been used.
What is the most used surfactant?
Anionic and nonionic surfactants are by far the most used surfactant types in the industry. Anionic surfactant finds use, especially in cleaning products like laundry detergents and shampoos. Nonionic surfactants on the other hand are often used as wetting agents and in the food industry.
Where is surfactant found?
Abstract. Pulmonary surfactant is a complex and highly surface active material composed of lipids and proteins which is found in the fluid lining the alveolar surface of the lungs.
What is a surfactant and what are its properties?
surfactant, also called surface-active agent, substance such as a detergent that, when added to a liquid, reduces its surface tension, thereby increasing its spreading and wetting properties. In the dyeing of textiles, surfactants help the dye penetrate the fabric evenly.
How are surfactants used in personal hygiene?
Surfactants also enable the fine dispersion of colour pigments in make-up and lipstick. They disperse perfumes in toilet waters, aftershaves and hair lotions and are found in hair dyes and hair care products as well as shaving creams and toothpastes.
What is surfactant used for?
Surfactants are compounds used in an array of cleaning products for their ability to lower the surface tension of water, in esse nce making the molecules slipperier, so they are less likely to stick to themselves and more likely to interact with oil and grease. Beyond soaps and detergents, surfactants are used in lubricants, inks, ...
Why do lungs produce surfactants?
The lungs produce surfactants at the cellular level to aid in the breathing process by helping keep airways open. Uses & Benefits. Safety Information.
Can soap be used as a surfactant?
Without surfactants, soaps wouldn’t mix with the water, but would just roll off the water, making the cleaning process much more difficult. Surfactants also are used as an ingredient in lubricants, such as shaving cream, where they allow razors to easily remove stubble and help limit irritation.
What is surface surfactant?
Surface Science Blog. Surfactants are the most versatile products of the chemical industry. There are utilized in every industrial area ranging from household detergents to drilling muds and food items to pharmaceuticals. The term surfactant comes from the word surface active agent. They are amphiphilic molecules and are thus absorbed in ...
Where does surfactant come from?
The term surfactant comes from the word surface active agent. They are amphiphilic molecules and are thus absorbed in the air-water interface. At the interface, they align themselves so that the hydrophobic part is in the air and the hydrophilic part is in water.
Why do surfactants absorb water?
Because of their amphiphilic nature, surfactants absorb at the air-water or oil-water interface. At the interface, surfactants align themselves so that the hydrophobic part is in the air (or oil) and the hydrophilic part in water.
What is the intermolecular force between surfactant and water?
For simplicity, let’s consider only the air-water interface. The cohesive forces between the water molecules are very strong making the surface tension of water high. As surfactants absorb they break these interactions. The intermolecular forces between surfactant and water molecule are much lower than between two water molecules ...
What is a surfactant called when it has a negative charge?
If it contains both positive and negative groups, then the surfactant is called zwitterionic. Anionic and nonionic surfactants are by far the most used surfactant types in the industry. Anionic surfactant finds use especially in cleaning products like ...
What happens to surface tension when surfactant concentration is high?
When the surfactant concentration is high, they form micelles. The point at which micelles are formed is called critical micelle concentration. The main purpose of the surfactants is to decrease ...
Is surfactant a hydrocarbon?
As said, surfactants are amphiphilic molecules that have hydrophobic and hydrophilic parts. The hydrophobic tail is a hydrocarbon, fluorocarbon or siloxane. Surfactants are typically classified based on their polar head as the hydrophobic tails are often similar. If the head group has no charge, the surfactant is called non-ionic.
What is a surfactant?
Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids, between a gas and a liquid, or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, or dispersants . The word "surfactant" is a blend of surface-active agent, coined c. 1950.
What is the most important surfactant?
The commercially most significant type of surfactants is currently the anionic surfactant LAS, which is widely used in cleaners and detergents.
What is the structure of surfactant phases in water?
Structure of surfactant phases in water. In the bulk aqueous phase, surfactants form aggregates, such as micelles, where the hydrophobic tails form the core of the aggregate and the hydrophilic heads are in contact with the surrounding liquid.
Why do surfactant ions remain in oil?
Schematic diagram of a micelle – the lipophilic tails of the surfactant ions remain inside the oil because they interact more strongly with oil than with water. The polar "heads" of the surfactant molecules coating the micelle interact more strongly with water, so they form a hydrophilic outer layer that forms a barrier between micelles. This inhibits the oil droplets, the hydrophobic cores of micelles, from merging into fewer, larger droplets ("emulsion breaking") of the micelle. The compounds that coat a micelle are typically amphiphilic in nature, meaning that micelles may be stable either as droplets of aprotic solvents such as oil in water, or as protic solvents such as water in oil. When the droplet is aprotic it is sometimes known as a reverse micelle.
Why are surfactants used in quantum dots?
Surfactants are used with quantum dots in order to manipulate the growth, assembly, and electrical properties of quantum dots, in addition to mediating reactions on their surfaces . Research is ongoing in how surfactants arrange on the surface of the quantum dots.
What is the classification of surfactants?
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 a net positive, or negative charge.
What is the importance of surfactant adsorption?
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 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 the elasticity and viscosity of the layer, play an important role in the stability of foams and emulsions.
What is a surfactant spray?
Surfactants, also referred to as wetting agents or spreader stickers, help your liquid lawn and garden products adhere to, or "wet", the foliage they are sprayed on, ensuring you get the most out of the products. Learn more about surfactants, why they are needed, and how to use one by reading below.
Why do plants need surfactants?
Surfactants help the chemical stick to the plant, penetrating the waxy cuticle to allow the plant to absorb the chemical and increase the product's effectiveness. Surfactants are not meant to be used on their own, as they often do not have any effect on plants one way or another by themselves.
How to mix surfactant and water?
Mix the product with water in a hand pump or backpack sprayer according to the product label's instructions. Add your surfactant in as well, then shake the sprayer (with the cap on) to agitate and thoroughly combine the solution. Then, apply your product and surfactant mixture according to the label.
What is oil concentrate?
Oil concentrates - Oil concentrates use specialty oils like paraffinic oil or orange oil combined with surfactants. The oil helps the surfactant interact and mix with certain chemicals and may be advertised to be used with insecticides, fertilizers, or fungicides.
What is non ionic surfactant?
Non-ionic surfactants - Non-ionic surfactants are neutral, meaning they have neither a positive nor a negative charge. Non-ionic surfactants are popular as surfactants as their neutral charge reduces the chance of having a reaction with the chemicals they are mixed with.
Why do you apply fungicide to plants?
When applying an insecticide, herbicide, or fungicide to your plant, you want to prevent your liquid chemical from rolling off the plant leaves, as that will be a waste of product and money and will not help the plant.
Can you mix oil concentrate with surfactant?
Be sure to read the product label to be sure your product can be mixed with an oil concentrate. Built-In surfactants - Many products formulated to be used on plants, like herbicides, will include a surfactant in their bottle. This eliminates the need to purchase and use an additional surfactant, one less product and step to worry about in your lawn ...
What is surfactant used for?
Surfactants are used to solubilize membrane-bound proteins from membranes and stabilize the proteins in solution. Therefore, the use of surfactants may be beneficial to stabilize membrane-bound proteins adsorbed on electrodes. Rusling’s group studied DET-type bioelectrocatalysis using insoluble surfactants such as didodecyldimethylammonium bromide, 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine, and PEDOT polystyrene sulfonate.107–111 It is believed that depositing these surfactants on the electrode can provide environments similar to those in the membranes of native cells (i.e., phospholipid bilayer membranes) on the electrode surface ( Fig. 7 ). Redox enzymes are embedded in the surfactant membrane and show DET-type catalytic responses. Furthermore, the surfactant membranes appear to inhibit adsorption of other macromolecules that coexist in DET-type enzyme solutions as contaminants and may inhibit the DET reaction. Both soluble proteins (myoglobin, cytochrome c, and hemoglobin) 107–111 and membrane-bound proteins (cytochrome P450) 107 have been used in these studies; however, there were no clear differences between the soluble and membrane-bound enzymes, that is, both types of proteins showed clear DET signals. Furthermore, DET responses were observed after coassembling heme-containing proteins and soluble surfactants (such as sodium dodecyl sulfate and Triton X) on bare or CNT-modified GC electrodes. 112,113 For soluble surfactants, micelle concentration is critically important to the preparation of surfactant membranes on the electrode surface. Membrane-bound H 2 ase codeposited with liposomes on Au electrodes shows a clear DET-type bioelectrocatalytic wave. 72 When His-tagged cytochrome c oxidase was adsorbed on a Ni-NTA-modified Au electrode and a bilayer environment was reconstituted by immersing the cytochrome c oxidase-adsorbed electrode in a liposome dispersion, DET-type catalytic response of cytochrome c oxidase was observed. 92,93 In these cases, membrane-bound enzymes are stabilized by the lipid bilayer. However, it remains unclear whether the surfactant is necessary for the adsorption of proteins. In fact, a large amount of surfactant inhibits the adsorption of proteins on electrodes 114,115; in such cases, the amount of surfactant should be decreased.
What are the characteristics of surfactants?
15.2 Characteristics and Classification of Surfactants. Surfactants are substances that create self-assembled molecular clusters called micelles in a solution (water or oil phase) and adsorb to the interface between a solution and a different phase (gases/solids). To show these two physical properties, a surfactant must have a chemical structure ...
What is the hydrophilic group of nonionic surfactants?
The hydrophilic group of nonionic surfactants is usually a polyoxyethylene group , but there are also nonionic surfactants with glyceryl groups or sorbitol groups, and nonionic surfactants with these different hydrophilic groups are also used depending on the application. Figure 15.1.
What is a surfactant aquifer remediation?
Surfactant -enhanced aquifer remediation (SEAR) has been proposed as a means of enhancing the removal of NAPL from contaminated sites. SEAR involves the injection of surfactant solutions to solubilize and mobilize NAPL constituents. The surfactant and contaminants are subsequently extracted through pumping wells. Various design approaches may be taken to SEAR, depending on the hydrogeological conditions and the physicochemical properties of the NAPL. The solubilization mechanism, which is at the heart of the SEAR process, is the formation in the groundwater of micelles, in which the molecules of the NAPL are dissolved and then transported by the groundwater. In the field, SEAR works similarly to pump-and-treat operations except that dilute surfactant solutions are injected into the contaminated aquifer and withdrawn together with the solubilized NAPLs.
What is the role of surfactant in printing?
Surfactants are another key ingredient in terms of delivering the pigment and the binder from the ink to the substrate through the print head. High HLB (hydrophilic and lipophilic balance) surfactants are used typically for aiding the colloidal stability of the systems, and low HLB surfactants are used to lower the surface tension, so the ink can wet the nozzle capillary to establish and maintain the meniscus at the nozzle tip. The importance of maintaining the meniscus at the nozzle tip both in the steady state and in the dynamic state during jetting cannot be overemphasized because it is so critical for start-up, reducing latency (defined as number of firings needed before the ink establishes the first stable drop of jetting), increasing the elapsed time between jetting without refreshing and ultimately long-term reliable continuous printing. For some print heads, reliable jetting or printing can be achieved even when the nozzle plate is wetted. This low HLB surfactant is also a major factor which determines the interaction between the ink and the substrate and therefore controls or affects wetting, bleeding, dot-gain, dot-quality and ultimately the image quality. Surfactants affect these properties through a physical parameter, namely surface tension (both static and dynamic). The most popular surfactants used for this purpose are relatively short-chain ethylene glycol nonionic surfactants such as the Air Products Surfynol TM line of products like Surfynol TM 465. Anionic surfactants such as Aerosol TM OT are also used.
What is nonionic surfactant?
Nonionic surfactants are surfactants that do not dissociate into ions in aqueous solutions, and they are subclassified depending on the type of their hydrophilic group ( Fig. 15.1 ). Common hydrophilic groups of ionic surfactants are carboxylate (–COO − ), sulfate (–OSO 3− ), sulfonate (SO 3− ), carboxybetaine (–NR 2 CH 2 COO − ), ...
What substance lowers the surface tension of water?
The substance which is able to lower the surface tension of water remarkably is termed a surfactant , as shown by curve C in Fig. 9.1. Since ∂ γ / ∂ c 2 < 0 for surfactants, their surface excess at the surface of water is positive according to the Gibbs equation, which means positive adsorption. Surfactants are widely used in practice, for example, emulsification, breaking of emulsion, foaming, defoaming, dispersion, flocculation, increasing of solubility, wetting, scale inhibition, and corrosion inhibition. As far as the chemical structure is concerned, a surfactant molecule has both a hydrophilic polar group and a hydrophobic nonpolar hydrocarbon chain on one molecule, as shown in Fig. 9.5, for example, CH 3 (CH 2) n OH (alcohol), CH 3 (CH 2) n COOH (carboxylic acid), and CH 3 (CH 2) n NH 2 (amine). Therefore, the molecule of the surfactant is always adsorbed at the surface of water, with the hydrophilic groups oriented toward the water phase and the hydrophobic hydrocarbon chains oriented away from the water phase. Due to the hydrophobic effect of the hydrocarbon chain, the oriented molecule of the surfactant can reduce the vertically inward composite force, thus decreasing the surface tension. The more molecules of the surfactant in the surface layer, the greater the decrease in surface tension. In the beginning, the surfactant added to water is less, thus the concentration is lower; the molecules of the surfactant may roughly lie flat on the surface of water but still have the orientation to some extent due to the repulsion between the hydrophobic chains and water as well as the attraction between polar groups and water. The situation is illustrated in Fig. 9.6 a. With the increase in concentration, the hydrocarbon chains become more and more oriented toward the air, as shown in Fig. 9.6 b. When the concentration reaches very high, the molecules arrange “side by side” at the surface, reaching the adsorption saturation, as shown in Fig. 9.6 c.
What is surfactant in cleaning?
Surfactants are a primary component of cleaning detergents. The word surfactant means surface active agent. As the name implies, surfactants stir up activity on the surface you are cleaning to help trap dirt and remove it from the surface. Surfactants have a hydrophobic (water-hating) tail and a hydrophilic (water-loving) head.
What is a cationic surfactant?
Cationic surfactants can also serve as antimicrobial agents, so they are often used in disinfectants. Cationic surfactants cannot be used with anionic surfactants.
What is the charge of amphoteric surfactants?
Amphoteric surfactants have a dual charge on their hydrophilic end, both positive and negative. The dual charges cancel each other out creating a net charge of zero, referred to as zwitterionic. The pH of any given solution will determine how the amphoteric surfactants react.
What is the cloud point of a nonionic surfactant?
The cloud point is the temperature at which the nonionic surfactant begins to separate from the cleaning solution, called phase separation. When this occurs, the cleaning solution becomes cloudy. This is considered the temperature for optimal detergency.
What are some examples of anionic surfactants?
While anionic surfactants are excellent for lifting and suspending particulate soils, they are not as good at emulsifying oily soils. Sulfates, sulfonates, and gluconates are examples of anionic surfactants.
Why are anionic surfactants used in soap?
The negative charge helps the surfactant molecules lift and suspend soils in micelles. Because they are able to attack a broad range of soils, anionic surfactants are used frequently in soaps and detergents. Anionic surfactants create a lot of foam when mixed.
Where is the detergency for foaming cleaners?
For low foaming cleaners, optimal detergency is at the cloud point; for foaming cleaners optimal detergency is either just below the cloud point or at the start of the cloud point . The agitation of low foaming cleaners is sufficient to prevent phase separation.
Why do surfactants work?
Surfactants work because they’re able to break the surface tension of the herbicide and leaf surface. This allows the spray to evenly coat leaf surfaces in an even sheen with no beading up or rolling off.
What is a surfactant in herbicides?
A surfactant, a combination of the words “surface active agent,” is an organic compound that is soluble in chemical solutions or water and allows mixtures to blend, adhere and work better.
How to survive a drought?
Prior to a period of drought, it is essential that you switch to a potassium-rich fertilizer and ditch the nitrogen formula. A potassium fertilizer will help to strengthen each blade of your lawn including the crown helping it to retain strength during periods of heat and dryness. During a drought, it is best to avoid using any pesticides or herbicides as they can leech the soil of excess moisture. To help retain moisture and provide extra nutrients during a drought you can spread a light coating of your clippings.
Do herbicides need surfactants?
Some herbicides actually need surfactants in order to work, but other products might already have surfactants added in. Make sure you read all labels thoroughly before adding anything to your herbicide. When looking for a surfactant to purchase to use with an herbicide, always look for a nonionic surfactant.
Overview
Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids, between a gas and a liquid, or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, or dispersants. The word "surfactant" is a blend of surface-active agent, coined c. 1950.
Agents that increase surface tension are "surface active" in the literal sense but are not called su…
Composition and structure
Surfactants are usually organic compounds that are amphiphilic, meaning they contain both hydrophobic groups (their tails) and hydrophilic groups (their heads). Therefore, a surfactant contains both a water-insoluble (or oil-soluble) component and a water-soluble component. Surfactants will diffuse in water and adsorb 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 hydrophobi…
In biology
The human body produces diverse surfactants. Pulmonary surfactant 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 Tekzim…
Safety and environmental risks
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 low LD50 (5 g/kg) and are essentially non-toxic, while the disinfectant alkylbenzyldimethylammonium chloride has an LD50 of 0.35 g/kg. Prolonged exposure to surfactants can irritate and damage the skin b…
Applications
The annual global production of surfactants was 13 million tons in 2008. In 2014, the world market for surfactants reached a volume of more than US $33 billion. Market researchers expect annual revenues to increase by 2.5% per year to around $40.4 billion until 2022. The commercially most significant type of surfactants is currently the anionic surfactant LAS, which is widely used in cleaners and detergents.
Classification
The "tails" of most surfactants are fairly similar, consisting of 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 t…
See also
• Anti-fog – Chemicals that prevent the condensation of water as small droplets on a surface
• Cleavable detergent
• Disodium cocoamphodiacetate
• Emulsion – Mixture of two or more liquids that are generally immiscible
External links
• Media related to Surfactants at Wikimedia Commons