surface active agents

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Surface Active Agents

Prepared By : Mazadul Hasan sheshirID: 201000040000813th Batch (session 2009-2013)Department : Wet Processing Technology Email: mazadulhasan@yahoo.comBlog : www. Textilelab.blogspot.com (visit)

Southeast University Department Of Textile Engineering

I/A 251,252 Tejgaon Dhaka Bangladesh

Prepared By :

©right

Surface Active Agents The term surfactant is a blend of surface

active agent. Surfactants are usually organic compounds that are amphiphilic, meaning they contain both hydrophobic groups (their "tails") and hydrophilic groups (their "heads").

when added to a liquid, reduces its surface tension, thereby increasing its spreading and wetting properties.

In the dyeing of textiles, surface-active agents help the dye penetrate the fabric evenly.

Application of Surfactants Detergents Fabric softener Emulsifiers and

Emulsions Paints Adhesives Inks Anti-fogging Dispersants Wetting Ski wax, snowboard

wax

Defoamers Agrochemical

formulations Herbicides some Insecticides

Biocides Shampoo Hair conditioners (after

shampoo) Spermicide Firefighting Foaming agents

Detergent

A detergent (as a noun; "detersive" means "cleaning" or "having cleaning properties"; adjective "detergency" indicates presence or degree of cleaning property) is a material intended to assist cleaning.

Today, detergent surfactants are made from a variety of petrochemicals (derived from petroleum) and/or oleochemicals (derived from fats and oils).

Although the cleansing action of soaps and detergents is similar, the detergents do not react as readily with hard water ions of calcium and magnesium. Detergent molecular structures consist of a long hydrocarbon chain and a water soluble ionic group.

Classification of detergents

1. Ionic detergent- Anionic detergent - Cationic detergent- Amphoteric detergent2. Nonionic detergent

Anionic detergents:

The detergents whichconsist negative ionic group are called anionic detergents. The majority are alky sulfates and others are generally known as alkyl benzene sulfonates.

Cationic detergents

The cationic classes of detergents have a positive ionic charge and are called "cationic" detergents. In addition to being good cleansing agents, they also possess germicidal properties which makes them useful in hospitals. Most of these detergents are derivatives of ammonia. A cationic detergent is most likely to be found in a shampoo or clothes "rinse".

Nonionic detergents Nonionic surfactant

molecules are produced by first converting the hydrocarbon to an alcohol and then reacting the fatty alcohol with ethylene oxide. They are not ionize in water. They are very popular in textile uses.

Advantages and disadvantages of synthetic detergents

Effective cleaning in hard water They are not precipitate as insoluble

Ca/Mg salts (gummy substance) on material

They are not very good detergent as soap

Incompatibility, in case of opposite ionic nature

Environmental hazard

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