““SurfactantsSurfactants””

^^^^SurfactantsSurfactants^^^^

Surfactants: are wetting agents that lower the surface tension of a liquid, allowing easier spreading, and lower the interfacial tension between two liquids.

**A surfactant or surface active agent is a substance that, A surfactant or surface active agent is a substance that, when dissolved in water, gives a product the ability to when dissolved in water, gives a product the ability to

remove dirt from surfaces such as the human skin, textiles, remove dirt from surfaces such as the human skin, textiles, and other solidsand other solids..

**Each surfactant molecule has a Each surfactant molecule has a hydrophilic (water-loving) head hydrophilic (water-loving) head that is attracted to water that is attracted to water molecules AND a hydrophobic molecules AND a hydrophobic (water-hating) tail that repels (water-hating) tail that repels water and simultaneously water and simultaneously attaches itself to oil and grease in attaches itself to oil and grease in dirtdirt

What does a surfactant actually doWhat does a surfactant actually do??

Surfactants are also referred to as wetting agents and foamers. Surfactants lower the surface tension of the medium in which it is dissolved. By lowering this interfacial tension between two media or interfaces (e.g. air/water, water/stain, stain/fabric)

Are surfactants of natural or Are surfactants of natural or synthetic originsynthetic origin? ?

They can be either. Surfactants from natural origin (vegetable or animal) are known as oleo-chemicals and are derived from sources such as palm oil or tallow. Surfactants from synthetic origin are known as petro-chemicals and are derived from petroleum.

Classification of surfactantsClassification of surfactants??

A_Ionic surfactant B_Non-ionic surfactants

Anionic

Cationic

Zwitterionic (amphoteric)

AnionicAnionic •*In solution, the head is negatively charged. This is

the most widely used type of surfactant for laundering, dishwashing liquids and shampoos because of its excellent cleaning properties and high

•(based on sulfate, sulfonate or carboxylate anions)

An example : Sodium dodecyl sulfate (SDS)

A_ Ionic surfactant

**The most commonly used anionic surfactants are alkyl The most commonly used anionic surfactants are alkyl sulphates, alkyl ethoxylate sulphates and soapssulphates, alkyl ethoxylate sulphates and soaps..

CationicCationic

*In solution, the head is positively charged.

( based on quaternary ammonium cations)

An example : Benzethonium chloride (BZT)

Zwitterionic (amphoteric)

*These surfactants are very mild, making them particularly suited for use in personal care and household cleaning products.

*They can be: _anionic (negatively charged),

_cationic (positively charged) or_non-ionic (no charge) in solution,

depending on the acidity or pH of the water.

**An exampleAn example of an amphoteric/zwitterionic of an amphoteric/zwitterionic surfactant is surfactant is alkyl betainealkyl betaine

e.g. :Cocamidopropyl betaine

B_ Non-ionic surfactantsB_ Non-ionic surfactants *These surfactants do not have an electrical

charge, which makes them resistant to water hardness deactivation.

*They are excellent grease removers that are used in laundry products, household cleaners and hand dishwashing liquids.

**The most commonly used non-ionic surfactants are The most commonly used non-ionic surfactants are ethers of fatty alcoholsethers of fatty alcohols

An example : Cocamide MEA

MicelleMicelle

*A micelle (rarely micella, plural micellae) is an aggregate of surfactant molecules dispersed in a liquid colloid.

* A typical micelle in aqueous solution forms a roughly spherical or globular aggregate with the hydrophilic "head" regions in contact with surrounding solvent, sequestering the hydrophobic tail regions in the

micelle center.

How do surfactants work in How do surfactants work in detaildetail??

Surfactants can work in three different ways:

a_ roll-up,

b_ emulsification, andc_ solubilization .

A_ Roll-up mechanismA_ Roll-up mechanism

The surfactant lowers the The surfactant lowers the oil/solution and fabric/solution oil/solution and fabric/solution interfacial tensions andinterfacial tensions and

in this wayin this way lifts the stain of lifts the stain of the fabricthe fabric..

B_ EmulsificationB_ Emulsification The surfactant lowers the oil-solution interfacial tension and makes easy emulsificationemulsification of the oily soils possible .

C_ SolubilizationC_ Solubilization Through interaction with the micelles of a Through interaction with the micelles of a surfactant in a solvent (water), a surfactant in a solvent (water), a substance spontaneously dissolves to substance spontaneously dissolves to form a stable and clear solutionform a stable and clear solution . .

Applications of SurfactantApplications of Surfactant

Surfactants play an important role in many practical applications and products, including:

DetergentDetergent *is a compound, or a

mixture of compounds, intended to assist cleaning. The term is often used to differentiate between soap and other chemical surfactants used for cleaning purposes.

Fabric softenerFabric softener (also called Fabric Conditioner )

*is used to prevent static cling and makes the fabric softer.

AnAn emulsifieremulsifier *(also known as an

emulgent or surfactant )is a

substance which stabilizes an emulsion.

An adhesiveAn adhesive *is a compound that adheres or bonds

two items together.

AnAn inkink *is a liquid containing various pigments

and/or dyes used for colouring a surface to render an image or text. Ink is used for drawing or writing with a

pen or brush.

AA laxativelaxative *is a preparation used for encouraging

defecation, or the expulsion of feces. Laxatives are most often taken to treat constipation.

**Wetting Wetting **Ski Wax Ski Wax **Snowboard Wax Snowboard Wax **Foaming Foaming **Defoaming Defoaming **Quantum dot coating Quantum dot coating **Biocides (Sanitizers) Biocides (Sanitizers) **Hair Conditioners (after Hair Conditioners (after shampoo) shampoo) **Spermicide (Nonoxynol 9) Spermicide (Nonoxynol 9)

Best wishes..

Thanks for your time..Thanks for your time..

Shaden Abal_khail

Abeer Al_smari

Deema Al_molaiki

Amani Al_moharram